Torqbyte Tech Blog

Using the Factory BMW T/MAP Sensors with the CM5-LTS

In most BMW applications with a CM5-LTS WMI controller, it is preferred to obtain boost readings by "teeing" into the factory TMAP sensor wiring. Below is the information on how to do this for several popular BMW TMAPs we have tested.

The numbers below are derived from a sample of one sensor each that we have tested. The numbers below may differ for individual sensors in different cars.

OEM Part No. 13627843531
Pressure Rating: 3.5Bar (Absolute) => 2.5Bar / 36PSI (Boost)

TorqTune Settings:

Slope: 19.533
Intercept: 247.991
Atmosphere: 251

Wire Connections:

Pinout for BMW 13627843531 13627551429 13627585493

//***************************************************

OEM Part No. 13627551429 (Old) / 13627585493 (New)
Pressure Rating: 2.5Bar (Absolute) => 1.5Bar / 21PSI (Boost)

TorqTune Settings:

Slope: 25.556
Intercept: 403.854
Atmosphere: 407

Wire Connections:

Pinout for BMW 13627843531 13627551429 13627585493

//***************************************************

OEM Part No. 13628637900
Pressure Rating: 2.5Bar (Absolute) => 1.5Bar / 21PSI (Boost)

TorqTune Settings:

Slope: 24.342
Intercept: 396.193
Atmosphere: 398

Wire Connections:

Pinout for BMW 13628637900

//***************************************************

OEM Part No. 13628637896
Pressure Rating: 4.0Bar (Absolute) => 3.0Bar / 45PSI (Boost)

TorqTune Settings:

Slope: 14.960
Intercept: 262.466
Atmosphere: 225

Wire Connections:

Pinout BMW Charge Air Pressure Sensor

Posted by Torq Byter_ on 16 November, 2019 Read more →

GPO - Generic Boost Cut Strategy

CM5 and CM5-LT are able implement 3 water methanol safety approaches and take action to cut boost whenever system trouble is detected in order to save the engine from overboost.

The 3 safety approaches are:

Approach 1: Activate one of the two General Purpose Outputs (GPOs) when one the two General Purpose Inputs (GPIs) is activated. This would apply when a fluid level sensor is connected to a GPI triggering it when the fluid level in the tank drops below the float sensor's level.

Approach 2: Activate one of the two GPOs when one of the spare voltage inputs drops below a certain voltage level. This would apply when a water methanol flow sensor with a voltage output is used and connected to one of the two analog voltage inputs (A or B). In this situation the GPO can be activated when the flow drops below a certain user-selected threshold which could mean the pump stopped or the tank ran out of fluid.

Approach 3: Activate one of the two GPOs when the pump current drops below or rises above some user-selected limits. Current that's too high could indicate the line is blocked (due to solenoid failure for example), while current that's too low could indicate the pump is freewheeling because the tank is empty. This mode requires some experimentation from set-up to set-up to dial in the exact threshold values.

These approaches are described in more detail HERE.

When trouble is detected and CM5/CM5-LT activates the configured GPO it's up to the rest of the system to take action in order to cut boost.

Most modern Electronic Boost Controllers (EBCs) have a dedicated "boost cut" or "boost override" input for implementing exactly this type of function. Interfacing the CM5/CM5-LT with such an EBC is described HERE.

However, some EBCs, like the Greddy Profec EBC don't have a dedicated input for cutting or overriding boost. Also, set-ups where factory boost-control is retained will also not have a boost-cut input on the Engine Computer that can just interface with the CM5/CM5-LT's GPO.

In these cases a different approach can be implemented where a relay is used to break the connection between the EBC (or the Engine Computer) and the boost solenoid. This is accomplished by connecting a relay in-line with one of the boost solenoid wires by using the relay's Normally Closed (NC) and Common (COM) terminals ensuring the boost solenoid and whatever is controlling it are connected by default whenever the relay is OFF. The relay itself is controlled by the appropriate GPO on the CM5/CM5-LT and whener WMI trouble is detected the GPO activates the relay which breaks the flow of current through the boost solenoid and causes it to close. This drops the boost to whatever the wastegate spring is set to with the aim of saving the engine by doing so.

The wiring diagram for this approach is shown here:

Generic Boost Cut Strategy

 

   CM5/CM5-LT Generic Boost-Cut Wiring Diagram

Posted by Torq Byter_ on 01 January, 2017 Read more →

GPO - Relay Control

CM5 and CM5-LT are equipped with two, pull-to-ground, General Purpose Outputs, GPO1 and GPO2 that can each be configured to switch ON or OFF either ABOVE or BELOW some setpoint.

This setpoint is a combination of engine RPM and either boost or analog voltage inputs A or B.

GPOs are limited to sinking 1.5A or less. In situations where higher current is required a relay must be used. This blog post covers relay control with the CM5/CM5-LT.

Since the GPOs are pull-to-ground outputs the correct wiring is to connect the relay's positive coil terminal to a switched ignition source that is a part of the vehicle's factory electrical system. This way, the relay's coil will only receive power when the ignition is ON. It's important to install a 2A fuse in-line with this connection and place it as close as possible to the ignition switched source where the power is being taken from.

The relay's negative coil terminal should be connected to the desired GPO on the CM5-LT.

Whenever a GPO on the CM5 activates, the relay will operate and connect (or disconnect) the signals you have attached to its Common (COM), Normally Open (NO) and Normally Closed (NC) terminals.

Torqbyte GPO Relay Control

   CM5/CM5-LT Relay Wiring Diagram

 Testing the Wiring

BEFORE using the relay, the wiring should be checked.

This is easily done using the Output Overrides on the main Settings Tab in TorqTune.

Turn the key to ACCESSORY, but don't start the engine.

Connect a USB cable between the CM5 and your Windows laptop and launch TorqTune. Ensure the unit is connected by looking for a green LED at the bottom right corner of TorqTune.

Once TorqTune shows the unit is connected navigate to the Output Duty Overrides section at the bottom left corner of the Settings tab.

Make sure you are close enough to the relay so you can her its "clicks".

Let's assume your relay is connected to GPO1. Enter 100 in the GPO1 duty field and hit Set. You should hear the relay "click" ON.

Now hit Reset. You should hear the relay "click" OFF.

This should confirm that your wiring is correct. Turn the ignition OFF.

TorqTune Configuration

This section assumes that your MAP sensor is properly calibrated and that all the key parameters on the Settings tab have been entered correctly.

Navigate to the appropriate GPO Table tab and from the Vertical Axis dropdown menu select whether you want to control the relay based on boost (i.e. the MAP sensor) or based on one of the two 0-5V analog inputs A or B.

We'll be using boost in this example.

From the Mode dropdown menu, select either the ON above setpoint, OFF below it mode or the OFF above setpoint, ON below it mode. Do not use the Duty table mode since the relays cannot be driven with a variable duty signal that is generated in this mode.

The other four modes would turn the GPO ON or OFF depending on whether or not there was a soft overcurrent or undercurrent fault detected on the MAIN or AUX pump output, but that is covered in a separate blog post HERE

In the ON above setpoint, OFF below it mode example shown below, the GPO (and the relay) will turn ON whenever the RPM and boost BOTH rise above the entered values (4 PSI and 1500 RPM, in this case). When either RPM or boost drop below their respective value the GPO (and the relay) will turn OFF.

If only RPM or only boost should be used for GPO control in this mode, simply enter zero (0) for the parameter that should be ignored.

In the OFF above setpoint, ON below it mode example shown below, the situation is reversed. The GPO (and the relay) will turn OFF whenever the RPM and boost BOTH rise above the entered values (4 PSI and 1500 RPM, in this case). When either RPM or boost drop below their respective value the GPO (and the relay) will turn ON.

If only RPM or only boost should be used for GPO control in this mode, simply enter maximum value allowable (by ticking the UP arrow as far as it will go) for the parameter that should be ignored.

In some set-ups it may be desirable to control the time delay (in milliseconds) between the instant the setpoint threshold is physically crossed and the instant the GPO (or the relay) turns ON or OFF. These two time periods are called Activation Delay and Deactivation Delay and implement a feature called hysteresis. You should only use this if necessary in your setup. If not required, just keep these values set to zero (0).

Posted by Torq Byter_ on 01 January, 2017 Read more →

GPO - Auxiliary Injector Control

CM5 and CM5-LT are equipped with two, pull-to-ground, General Purpose Outputs, GPO1 and GPO2 that can each be controlled with a separate 3D 16x16 cell duty table. In this mode the outputs are pulsed at a fixed frequency of 30Hz.

One possible use for these outputs is controlling auxiliary injectors that provide supplemental fuelling in direct injected applications.

Each GPO can sink up to 1.5A, which rules using low-impedance injectors since those injectors all draw more than 1.5A.

The negative terminal of an auxiliary high-impedance injector is connected to one of the CM5's GPOs. The positive terminal is connected to a relay or fuse that goes HOT whenever the ignition is ON. This would be part of the vehicle's existing electrical system. It is important to set things up so that injector see any power when the engine is off. This enusres the injector doesn't accidentally turn on when the engine is OFF. It is also important to use a 2A fuse in line with the injectors power feed. This fuse must be installed as close to the power source as possible.

Whenever a GPO on the CM5 activates, the injector will open and inject fuel.

GPO Injector Control - Direct

In vehicles where the factory switched ignition circuit doesn't have enough spare capacity to deal with an additional 2A load in the form of the auxiliary injector, a relay must be added and connected as follows:

GPO Injector Control - Relay

Note that the relay requires its own 2A fuse placed right at the battery.

In this set-up the ignition circuit only needs to power the relay coil which is a very light load. With the ignition on, the relay is automatically activated and the battery power from the Normally Open (NO) relay terminal 87 is connected to the Common (COM) terminal 30 supplying power to the injector.

As before, whenever GPO on the CM5 activates and provides a path to ground the injector will open and inject fuel.

   CM5/CM5-LT Injector Wiring Diagram

Testing the Wiring

BEFORE connecting the pressurized fuel line to the injector, the wiring should be checked.

This is easily done using the Output Overrides on the main Settings Tab in TorqTune.

Turn the key to ACCESSORY, but don't start the engine.

Connect a USB cable between the CM5 and your Windows laptop and launch TorqTune. Ensure the unit is connected by looking for a green LED at the bottom right corner of TorqTune.

Once TorqTune shows the unit is connected navigate to the Output Duty Overrides section at the bottom left corner of the Settings tab.

Have a helper, who is wearing safety glasses, near the injector and ask him/her to let you know when the injector "clicks".

Let's assume your injector is connected to GPO1. Enter 100 in the GPO1 duty field and hit Set. The helper should hear the injector "click" ON. Don't run the injector like this for more than a couple of seconds !!!

Now hit Reset. The helper should hear the injector "click" OFF.

This should confirm that your wiring is correct. Turn the ignition OFF.

TorqTune Configuration

This section assumes that your MAP sensor is properly calibrated and that all the key parameters on the Settings tab have been entered correctly.

Navigate to the appropriate GPO Table tab and place that GPO in Duty table mode. DO NOT select any of the other modes since they only switch hard ON (i.e. at 100% duty) which is intended for driving solenoids or relays but not for driving injectors.

 

Next, set the RPM and Boost values above which the table should be "active". This doesn't mean that the injector will turn on when both of these values are exceeded. It just means that the unit won't even look at the duty table values below these limits. You typically want to set the RPM value to something well above idle and the Boost value somewhere above your wastegate spring pressure.

Here we're using 10 PSI and 1500 RPM ensuring the table isn't even looked at when the boost is below 10 PSI or engine speed is less than 1500 RPM. You should use values here that make sense in your set-up.

Next fill the table with duty cell values that make sense for your set-up. This will depend largely on your tuning, the size of auxiliary injector, your fuel pressure and the fuelling requirements of your set-up. Keep in mind that the CM5-LT's output is not synchronized to the firing events of the main injectors, so don't go too high on the entered duty values especially low in the RPM band.

Here is a sample table from a big turbo TFSI set-up running a 1000cc High Impedance auxiliary injector.

 

 

When you are happy with your table hit Write All to apply your calibration to the unit. Don't forget to SaveAs and store your calibration files so you can go back to a previous version if something goes wrong.

Enjoy the extra fuelling.

Posted by Torq Byter_ on 30 December, 2016 Read more →

Using an LED to Show WMI Activity

Many users prefer to install a Light Emitting Diode (LED), somewhere on the dash, in order to show the activity of their Water Methanol Injection (WMI) system.

With the CM5/CM5-LT this can be easily accomplished using two basic approaches.

First some LED theory...

A LED is a two-terminal, polarized device. That means that its polarity must be considered when it's installed or it will not turn on. The two terminals are called CATHODE and ANODE. When the CATHODE is connected to GROUND and the ANODE is connected to a positive voltage, the LED will turn on.

LED Polarity

The CM5/CM5-LT has two General Purpose Outputs (GPO1 and GPO2) which can be used to control an LED. These outputs are "pull-to-ground" type which means that whatever load is connect to a GPO it will be connected to ground whenever that GPO is active.

So the LED's ANODE must be connected to a positive voltage while its CATHODE must be connected to the GPO on the CM5/CM5-LT what will be used to control it.

The positive voltage in the diagram shown above can be either 5Vdc that is taken from one of the spare RED (5Vdc) wires on the CM5/CM5-LT's Input/Output connector, or it can be 12Vdc sourced from a switched and fuse-protected connection somewhere else in the vehicle. LEDs draw very little current (around 0.02A) so they won't likely overload an existing ignition-switched 12Vdc circuit in the car.

Majority of LEDs operate at around 2Vdc. This is called their Forward Voltage. In order to run an LED from 5Vdc or 12Vdc, an in-line (aka series) resistor is required, which will drop the higher voltage to the 2Vdc level the LED can operate at. Connecting an LED directly to 5Vdc or 12Vdc without a series resistor will destroy the LED.

If using a regular LED such as the one described above, the following series resistor is recommended for 5Vdc operation:

and for 12Vdc operation:

 

There are many LEDs that come with a built-in series resistor that can be safely operated from from 5Vdc or 12Vdc eliminating the need for adding your own resistors shown above.

Here are some examples of LEDs that come with a threaded metal bezel and 6" long lead wires, which greatly simplify dash mounting:

L60D-G5-W (Green 5Vdc)
L60D-G12-W (Green 12Vdc)

L60D-R5-W (Red 5Vdc)
L60D-R12-W (Red 12Vdc)

L60D-A5-W (Yellow 5Vdc)
L60D-A12-W (Yellow 12Vdc)

There are many other colors and bezel styles available.

There are two basic LED indication modes that can be implemented in TorqTune to show WMI activity:

1. Hard ON/OFF LED Operation - The LED is fully ON when the pump is running and fully OFF when the pump is OFF.

2. Pump Duty-Matched LED Operation - The LED is operated with the same duty as the pump. This causes the LED to flash faster (i.e. get brighter) or slower (i.e. get dimmer) depending on the pump's duty.

Assuming the LED is correctly wired to GPO1 and assuming the following table is used for WMI pump control on the CM5/CM5-LT's MAIN output here is how the two approaches can be realized.

1. Hard ON/OFF LED Operation

To have the LED turn ON when the pump starts we need to look at the table entered on the Main Table tab. This will obviously vary from set-up to set-up, but in this example we can see the pump is off at 2500 RPM or less and 6 PSI of boost or less.

The CM5/CM-LT will start the pump as soon as these two values are exceeded, so on the GPO1 settings screen we should:

1. Select the mode ON above setpoint, OFF below it from the GPO1 control dropdown menu.
2. Set value in the MAP sensor is equal to or greater than field to 6.0 PSI.
3. Set value in the Engine Speed is equal to or greater than field to 2500 RPM.

With these settings applied the LED will turn on as soon as the pump duty is non-zero and will stay ON regardless of the actual pump duty.

2. Pump Duty-Matched LED Operation

To have the LED flash faster or slower (i.e. dim and brighten) in relation to actual pump duty, simply enter all the same settings (including the table cell values) on the GPO1 Table tab as were entered on the Main Table.

Main Table:

GPO1 Table:

With these settings applied the GPO1 duty will track that of the Main output and the LED will provide a visual indicator of the relative magnitude of the pump's duty.

 

Posted by Torq Byter_ on 30 October, 2016 Read more →

Boost Cut Strategy for the BMW N54 Engine

CM5 and CM5-LT controllers can be configured to detect various issues with the water methanol injection system and trigger one of the General Purpose Outputs (GPO1 or GPO2) to activate and cause an external boost control system to dump the turbocharger boost to safe levels in order to protect the engine.

These strategies are described HERE.

Usually this trigger is fed into an electronic boost controller (EBC) as described HERE.

However, getting the CM5/CM5-LT to dump the excess boost can also be accomplished in set-ups where the turbocharger waste gates are controller by the factory engine computer (aka the Digital Motor Electronics or DME).

The approach involves inserting a relay in-line with the signal wire between the wastegate solenoid and the DME. The relay contacts that are normally closed (NC) are used, so that when the relay is de-energized and the CM5-LT's GPO is not active (i.e. no WMI trouble is detected) the DME stays connected to the wastegate solenoid as intended.

BMW N54 Boost Cut Diagram

However, when the GPO on the CM5-LT activates the relay, it breaks the connection between the wastegate solenoid and the DME. This causes the wastegate solenoid to close and the turbocharger pressure to drop to the level determined by the mechanical rating of the wastegate spring.

BMW's N54 straight-6 DOHC has two wastegate valves. The PDF drawing below shows a detailed approach to cut boost via both valves. It includes a list of inexpensive, waterproof parts that can be used to implement this approach.

   BMW N54 Boost Cut Diagram

Posted by Torq Byter_ on 03 September, 2016 Read more →

Wiring Tutorial: Unit Power and Ground

Torqbyte PM3 and CM5/CM5-LT units are intended for driving heavy electrical loads. This makes proper power and ground wiring absolutely essential. Poor or inadequate wiring can prevent the unit from operating properly (at best) or could cause a fire, property damage, injury or death. If the installer is not familiar with basic electrical theory, lacks the proper assembly tools, or is not familiar with the target vehicle's electric system, the installation should be referred to an experienced professional.

In this post we will look at several options that can be used to provide proper power and ground wiring for your Torqbyte unit(s).

Before we get into all the details, let's first address some Frequently Asked Questions:

Q. Do I need to install a fuse?
A. Yes, you do.

Q. Why?
A. Fuses protect wires from overheating and bursting into flames that could happen if a power wire gets shorted to ground with nothing but the wire's resistance to limit the huge current that will start to flow. Any time you have a power wire running any significant length away from a power source (i.e. the battery), you should install a fuse right at the power source.

Q. Where should I install the fuse?
A. To be effective the fuse MUST be located as close to the battery as possible. Any length of wire between the battery and the fuse is no protected, so it's important to keep this length as short as possible.

Q. My PM3 already has a fuse, do I still need a fuse on the power input wire?
A. Yes, you do.

Q. Why?
A. The 40A fuse built into the PM3 is there to protect the PM3 and the wiring between the PM3 and the fuel pump against any shorts on the PM3's Power Out connection. This fuse provides NO protection against the faults (shorts) on the incoming power wire between the battery and the PM3.

Q. Does the PM3 Plug-n-Play harness take care of input power?
A. No. It only tees into the connection between the PM3, the pump and the factory J538 pump controller. You will need to add your own fused power wiring even when using a PM3 Plug-n-Play harness.

Q. That's not very Plug-n-Play, is it?
A. It's Plug-n-Play enough to take care of the two more challenging connections between the PM3 and the factory J538 PWM module and between the PM3 and the fuel sender without the need to disturb the factory wiring.

Q. Do you include a fuse in your PM3 kit or your CM5/CM5-LT kits?
A. No, we don't.

Q. Why?
A. Our products can be installed in many makes and models - some with OEM wiring and others that have been rewired with completely custom electrical set-ups. We can't supply a fuse that will work in every target application and configuration.

Q. Why do I have to supply my own wire?
A. Our products can be installed in many makes and models. We can't supply a long enough length of wire that will work in every target application and every wire-routing configuration.

Q. The other guys aren't asking me to buy my own wire. Why are you?
A. We only use the SXL automotive wire that meets the SAE J1127 standard, while most of the other guys use cheap home appliance wire (as in wire meant for use in fridges and washing machines) which is totally unsuitable for use in the automotive electrical environment. Don't believe us? Check out the other guys' wiring. If it has AWM or MTW printed on the insulation, it's not automotive wire.

The SXL-10 wire we use is a heavy gauge automotive wire that also has an extra thick outer jacket. The copper conductor thickness combined with the thicker than usual insulation makes this wire fairly heavy and relatively expensive. Including a pre-packaged length in each kit that is sufficiently long for the longest target vehicle (say a truck) would unnecessarily increase the product costs and shipping costs for a majority of customers who wouldn't otherwise require that much wire. It would also be kind of wasteful.

Q. Can I buy this wire from you?
A. You can, but why would you want to pay us a reseller's premium - especially if you live in the US? We purchase the SXL-10 wire from AWC Wire in the United States, but there are also many other good suppliers that you can buy from. By the time we factor in shipping, brokerage, taxes, handling, etc... our price to you could easily be twice or three times what it would cost you just to order it yourself. It's always best to just go directly to the source and skip the middleman.

Q. I don't live in the US or Canada. Where can I get this 10AWG (aka 10 Gauge) wire?
A. AWG stands for American Wire Gauge, so the 10AWG wire is generally specific to the North American geographic market. While you may be able to get 10AWG wire in your country, or may be able to order it online and have it shipped to you from a US supplier, we would recommend that you source the functionally equivalent European 6.0mm^2 LEONI Mocar® 125 XE or LEONI Mocar® 180 E automotive wire.

Q. The other guys aren't asking me to buy additional ring terminals, wire splices and other bits. Why are you?
A. Again our products can be installed in many different makes and models and by different installers who prefer to take different approaches when doing the install, such as using only their preferred splices or ring terminals. We couldn't possibly include all the bits and pieces that would work in every situation.

Q. Can I buy the extra bits and pieces from you?
A. You can, but as with the wire, why would you want to pay us a reseller's premium - especially if you live in the US? We purchase parts like these from electronics distributors like DigiKey, Mouser, Newark, Arrow, AvnetE-SonicTTI who are all mostly based in the United States. By the time we add shipping, brokerage, handling, etc... our price to you could easily be twice or three times what it would cost you just to order it yourself from one of the distributors listed above.

Q. I don't live in the US or Canada. Where can I order these extra bits and pieces?
A. Almost all of the electronic distributors listed above, particularly DigiKey, Mouser and Newark have physical offices and serve customers in many different countries throughout the world. We would recommend sourcing the required material locally to keep your costs down.

Q. Should I crimp or solder?
A. Always crimp. Never solder. Almost every automotive manufacturer prohibits the practice of soldering wires. The primary reason is that soldering can make copper brittle and affect the long-term reliability of the solder joint in a high vibration automotive environment. Crimped joints are mechanical and electrically superior, anyways. Don't solder.

Q. The recommended crimping tools (discussed at the bottom of this post) are quite expensive. I'd like to avoid paying that much money for a one-time use tool. Is there any other way that I can crimp these wire splices and terminals?
A. You are absolutely right that those tools are pretty expensive if you don't think that will use them more then once or twice. As with anything, there is always a different way to do something. Will that other approach produce results that are the same, better or worse than what can be achieved when using the recommended tools and procedures? We don't know. So we can't recommend anything that we haven't tried and that may conflict with the manufacturer's recommendations.

Q. This is all great to know, but I don't have time to read all this and even less time to make my own power wiring. Can you custom-make all the necessary wiring for me and just send me a ready-to-install harness?
A. Absolutely. We have all the materials and manufacturer-recommended tooling in-house and all we need from you is a napkin sketch, a few measurements.

Alright... Let's get started.

We will make a number of references here to Volkswagen and Audi vehicles just to illustrate the relevant topics. However, the concepts described below can be easily extended to a vast majority of modern vehicles.

We will focus our attention on the fuse box in the engine compartment because it is the most convenient location from which to pick up battery power. The reason that fuse box is a good starting place is that it comes with spare wire guides, studs/fasteners and a protective cover which will protect the new wiring and ensure the installation looks clean and neat when everything is put back together. Although this discussion is most applicable to vehicles with a front-mounted battery, the concepts are the same for vehicles with a trunk-mounted battery.

The fuse box in question is shown below:

Power Wiring Front Battery Option A

If you are installing the power wiring on a VAG vehicle that comes with a power distribution module with integrated fuses VW Part No. 1K0 937 829 (A), your job will be relatively simple.

The rightmost 40A fuse on this module is usually not used in the cars that use it. That 40A also happens to be the exact value that we need.

Note: Only use the 40A location !!! Anything with a rating higher than 40A will not protect your 10AWG wiring.

As we can see in the vehicle shown below, the rightmost 40A fuse is not used and the output end of the fuse even has an M5 stud that can receive our power wire.

The first thing you'll need to get is a yellow (10AWG) ring terminal (or ring lug) with a hole that can accept an M5 stud.

Although you can use whatever ring terminal you want we recommend either a TE Part No. B-106-1503 which is a heat-shrinkable and sealed ring terminal from their Dura-Seal product line or TE Part No. 130171 which is an unsealed terminal from their PIDG product line.

The Dura-Seal ring terminal can be purchased from E-Sonic.
The PIDG ring terminal can be purchased from DigiKey or Newark.

It should be noted that the other ring terminals in the fuse box are not sealed so it's up to you if you want to keep everything unsealed like the OEM or opt for a sealed terminal.

Using the recommended crimping tool (discussed at the bottom of this post), crimp the ring lug onto the 10AWG wire that you have previously run from the unit's location out to the fuse box. If you are using sealing ring lug, don't forget to heat shrink the insulation until the internal adhesive flows to form a seal around the wire (more on this at the bottom of this post).

The next thing that's required is an M5 nut. You can use a VW Part No. N 101 181 02  which is a self-locking, shouldered M5 hex nut used on other fuses in the fuse box, or you can use a regular stainless steel M5 hex nut and an M5 split lock-washer (Don't forget the lock-washer).

Your final configuration should something like this:

 

Power Wiring Front Battery Option B

If that rightmost integrated 40A fuse is unavailable,

or your fuse box doesn't even come with an integrated fuse module

but there is an unused M5 stud available, then you can still achieve the same result described in Option A, except that you will need to provide your own 40A fuse and some hardware to keep everything in place.

The first thing you'll need to get is that 40A fuse.

You can order this fuse from your local VW/Audi dealer under VAG Part No. N 10525501 or you can order it from one of the online electronics distributors using the manufacturer's Part No. 153.5631.5401. This LittelFuse part is available from DigiKey or Mouser.

As with Option A, you will need an M5 nut to secure the fuse to the M5 stud in the fuse box. You can order a VW Part No. N 101 181 02  which is a self-locking, shouldered M5 hex nut used on other fuses in the fuse box, or you can just use a regular stainless steel M5 hex nut and a stainless M5 split lock-washer. (Don't forget the lock-washer unless you are using the VW hex nut).

Again you will need an M5 ring terminal and, as before, we recommend using a TE Part No. B-106-1503 which is a heat-shrinkable and sealed ring terminal from their Dura-Seal product line or a TE Part No. 130171 which is an unsealed terminal from their PIDG product line.

The recommended Dura-Seal ring terminal can be purchased from E-Sonic.
The recommended PIDG ring terminal can be purchased from DigiKey or Newark.

It should be mentioned that other ring terminals in the fuse box are not sealed so it's up to you if you want to keep everything unsealed like OEM or use a sealed terminal.

Using the recommended crimping tool (discussed at the bottom of this post), crimp the ring lug onto the 10AWG wire that you have previously run from the unit's location out to the fuse box. If you are using sealing ring lug, don't forget to heat shrink the insulation until the internal adhesive flows to form a seal around the wire (more on this at the bottom of this post).

Finally, you'll need a nut and bolt to connect your ring lug to the other side of the fuse. You can order a shouldered M5x13.5mm bolt VW Part No. 1K0 919 625 and a second self-locking, shouldered M5 hex nut VW Part No. N 101 181 02 or you can just buy a stainless M5 Hex Bolt (about 14mm long), a matching M5 split locking washer and a matching M5 hex nut.

Your final configuration should something like this:

 When everything is in place, your final set-up should look something like this:

 

Power Wiring Front Battery Option C

If the vehicle you are working on does not have a fuse box similar to the one described above, the last remaining option is to connect the power wire directly to the battery's +ve terminal. This is the traditional approach used when installing new electrical equipment in a vehicle and, if done properly, it will still produce a very clean and reliable end result.

To start you will need a covered automotive inline fuse holder and a corresponding 40A automotive fuse.

We recommend using a LittelFuse fuse holder Part No. FHJC1001G, which is shown below.

 

This fuse holder can be purchased from DigiKey or Mouser.

The corresponding 40A fuse that fits inside this fuse holder is LittelFuse Part No. 0895040, which is shown below.

This 40A fuse can be purchased from DigiKey or Mouser.

While one of the free-hanging wires on the fuse holder will be connected to the battery with a ring terminal, the other wire will need to be joined to the positive wire that goes out to the unit. To join the fuse holder's "output" wire to your poitive wire run going to the unit, you will also need a yellow (10AWG) sealed wire splice. You can buy a yellow 10AWG splice from your local VW/Audi dealer under VAG Part No. 000 979 943 , but you will have to confirm with them what crimping tool you should be using, because we don't know who makes the splice VW sells nor what is their recommended crimping tool. On the other hand, you can get a slightly better quality yellow 10AWG wire splice from your local General Motors dealer under GM Part No. 19168448, which can be used with the same ratcheting crimping tool as the Dura-Seal splices and contacts described at the bottom of this post. If you'd rather not buy parts from a dealer, we recommend using a TE Part No. D-406-0003, which is a heat-shrinkable and sealed wire splice from TE's Dura-Seal product line.

This Dura-Seal wire splice can be purchased from DigiKey or Mouser.

The last item that you will need is a ring terminal with an opening that can accommodate the diameter of the bolt on your battery's positive terminal.

As with the other two options, we recommend either a sealed ring terminal from TE's Dura-Seal product line or an unsealed terminal from their PIDG product line.

All the 10AWG-compatible ring terminals from TE's sealed Dura-Seal product line are shown below:

All the 10AWG-compatible ring terminals from TE's unsealed PIDG product line are shown below:

Once you have selected a ring terminal part number from the above tables that works with the hardware on your battery's +ve terminal, one of the quickest ways to check where you can buy it, is to enter its part number in the Octopart Search Engine which will show you the current stock of that part at nearly every electronics distributor.

Your final configuration should look something like this:

 

You should cover the new power wire with some sort of a protective polyester braid or wire loom. Obviously you should not run this wire near any sources of high heat nor any moving parts that may wear through the insulation over time. Also, any time a wire is passed through a piece of metal (like your firewall) it should go through a grommet or a cord grip protect the wire's insulation from getting cut by the sharp edges of the opening that it's passing through.

 

Power Wiring Rear Battery

If the vehicle you are working on has a trunk-mounted battery, such as a 2011 Audi A4, the +ve battery terminal assembly attachment may already have a location for a spare fuse that you can use.

The first thing you'll need to get is that 40A fuse.

You can order this fuse from your local VW/Audi dealer under VAG Part No. N 10424902 or you can order it from one of the online electronics distributors using the fuse manufacturer's Part No. 156.5677.5401. This LittelFuse part is available from Mouser.

You will need an M6 ring terminal and, as before, we recommend using a TE Part No. B-106-1603 which is a heat-shrinkable and sealed ring terminal from their Dura-Seal product line or a TE Part No. 320569 which is an unsealed terminal from their PIDG product line.

The recommended Dura-Seal ring terminal can be purchased from E-Sonic.
The recommended PIDG ring terminal can be purchased from DigiKey or Newark.

Finally, you'll need two M6 nuts to bolt down the fuse and the ring terminal to the two M6 studs on the battery's +ve terminal block. You can order a flanged self-locking M6 hex nut VW Part No. N 904 880 05.

Alternately you can just buy a stainless steel M6 Hex nut and a matching M6 split locking washer (don't forget the split locking washer if you are using regular "hardware store" M6 nuts).

Your final configuration should something like this:

 

Ground Wiring

At this point, you should have a pretty good idea about the best way to bring fused power to your Torqbyte unit. The next thing we will focus on is grounding.

The ground connection should not be routed all the way to the battery's -ve terminal, unless the unit is physically very close to the battery, as it might be in the case of a trunk-mounted PM3 in a vehicle (like and Audi A3) that has a trunk-mounted battery.

The ground connection should be as short as possible and just like the +ve power connection the ground connection should be made using 10AWG wire. Obviously do your best to color code the wires based on their function. Use RED wire for power and BLACK wire for ground. This is a good practice and will make your (or someone else's) life easire of you ever have to troubleshoot this wiring in the future.

A technical service wiring diagram for most vehicles shows the factory grounding points throughout the vehicle. You should try to use one of those grounding points unless they are not very accessible or unless you are very confident that you have found another ground connection point that is going to work (i.e. it makes a good electrical contact with the car's chassis).

Here are some examples of potential chassis grounding points in a couple of VAG vehicles.

In a 2012 VW Golf GTI, one of these two points can be used. There are other suitable grounding points that are not shown here.

In a 2012 Audi A3, one of these points can be used. As before, there are other suitable grounding points that are not shown here.

In a 2011 Audi A4, any one of these three grounding points in the spare wheel well can be used for grounding.

Once a grounding point is selected, it's important to measure the diameter of the protruding stud or the grounding bolt and select a proper ring terminal from one of the two tables shown above. Typically Volkswagen uses M8 studs for grounding points in which case you should use.

Although you can use whatever ring terminal you want, we recommend either a TE Part No. B-106-1803 which is a heat-shrinkable and sealed ring terminal from their Dura-Seal product line or TE Part No. 2-35111-1 which is an unsealed terminal from their PIDG product line.

The Dura-Seal ring terminal can be purchased from E-Sonic.
The PIDG ring terminal can be purchased from DigiKey or Newark

With the right ring terminal on hand, the next thing that is required is to prep the mounting location to receive your ground wire ring terminal. While some of these grounding points will be clean, paint -free and otherwise good-to-go, you may select a grounding location which may be oily, dirty or might be painted. Since both the PM3 and the CM5/CM5-LT return a lot of current into the chassis ground, a very good electrical connection is a MUST. Shown below are a few notes on how to prep a painted stud located in the trunk of a 2012 VW Golf GTI.

If the chosen grounding location requires extra hardware (a nut and a split locking washer) you will need to get those as well in order to complete your installation. Once all the pieces are on hand, your final configuration should look like this:

Crimping Tools and Assembly Notes

PIDG Product Line (Unsealed)

The recommended ratcheting hand crimper for PIDG wire terminals is the TE Pro-Crimper III Part No. 58433-3.

Pro-Crimper III for PIDG terminals can be purchased from DigiKey.

Wires that will be crimped into a PIDG ring terminal need to have a strip length of 8.3cm (0.328").

Some manufacturer's notes on the assembly of PIDG terminals are shown below.

 

Dura-Seal Product Line (Sealed)

The recommended ratcheting crimper for Dura-Seal wire splices and Dura-Seal ring terminals is TE Part No. AD-1522. It's worth mentioning that the General Motors Tool No. J-38125-8 (or GM Part No. 12085115) is interchangeable with AD-1522.

AD-1522  for Dura-Seal terminals can be purchased from Mouser.

Wires that will be crimped into a Dura-Seal wire splice need to to have a strip length of 8.5mm (0.335").
Wires that will be crimped into a Dura-Seal terminal need to have a strip length of 7.0mm (0.275").

Some manufacturer's notes on the assembly of Dura-Seal splices and terminals are shown below.

Posted by Torq Byter_ on 10 November, 2015 Read more →

CM5 RPM Signal Source: VAG Applications

CM5 and CM5-LT require a clean (i.e. free of electrical noise) square RPM signal source that is synchronized to engine speed and that alternates between 0V (GND) and 5V or 0V (GND) and 12V.

If a signal that swings higher than 12V or significantly lower than 0V (i.e. a negative voltage) is fed into the CM5, the unit could get damaged. If the signal is noisy the RPM values the unit works out will not be accurate - they may jump around, drop out or periodically register as very high RPM values.

Here is an example of a noisy RPM signal:

Noisy RPM Signal

Here is an example of a clean RPM signal:

Clean RPM Signal

The unit and its firmware include some RPM filtering and hardware protection, but since the unit uses the calculated RPM value as the basis for duty control in nearly all of its output modes, a good and reliable RPM signal is a MUST to ensure trouble-free unit operation.

Option 1 - the preferred option !!!

RPM Coil On Plug Pickup

A good quality 0-5V signal can be obtained up by teeing into one of the wires between the ECU and the Coil On Plug modules found on newer models (N70,N127,N291,N292 aka Ignition Coils with Power Output Stage) or Ignition Control modules that were used on some older models (N122, N192 aka Power Output Stage Module).

It's best to tee into the wire as close to the ECU as possible since the ECU is the source of the signal and the coil is the sink, but either location will work. If the ECU wiring is not accessible the signal can be picked up at any of the Coils On Plug as shown.

Coil On Plug RPM Pickup

Here are the recommended Option 1 RPM signal pickup locations for several common VAG engines. Only one of the locations marked with the red "RPM arrow" below should be used.

RS7 RPM Pickup 

Option 2 - "ok" if no other option is available.

Injector RPM Pickup

A 0-12V signal can be picked up by teeing into one of the wires between the ECU and an injector.

Option 1 is preferred because these signals are generated by push-pull logic inside the ECU, which means that the RPM signal will be very clean. In Option 2, the ECU is switching an inductive load (the injector coil) on-off. Inductive load switching is generally a source of significant electrical noise. Depending on the particular ECU's internal electronics, on injector coil characteristics, as well as the length and state of the vehicle's wiring this signal may or may not be good enough to use. Unfortunately, the only true way to tell if this option will work is to look at the signal with an oscilloscope. Since most users won't have access to such equipment, it is strongly recommended that only Option 1 be considered whenever possible.

Wire Routing (IMPORTANT !!!)

The RPM wire tee should be made as close to the ECU as possible and it should be routed so that it is NEVER running alongside (i.e. parallel) or bundled with any other wires. This is ESPECIALLY true for noisy wires like the CM5's power wires, pump output wires, J538 output wires (if that option is used), etc. The reason is that any of these noisy wires will couple their electrical noise onto the RPM wire and corrupt the RPM signal . This will cause the CM5-LT to read false RPM values which will result in erratic and unexpected operation.

Don't bundle the RPM Signal with these signals

The CM5 or CM5-LT User Manuals shows a table showing different wire groups that should or must not be bundled together and allowed to run next to each other for long distances.

The CM5 and CM5-LT manuals state:

The diagram below shows how the unit wiring should be grouped. Some wires carry switching signals which are very noisy and can corrupt other sensitive signals and cause the unit to interpret false pressure readings or derive erroneous RPM values. The unit provides extensive hardware and software signal conditioning mechanisms to minimize the effects of noise-induced problems on its sensitive signal lines, but the user is cautioned to NEVER bundle together or run parallel to each other for any considerable distance, any wires from different Wire Groups shown below – especially anything from Group A together with or parallel to anything from Groups E or F.

CM5 Wire Groups

Posted by Torq Byter_ on 07 November, 2015 Read more →

TorqTune Video Tutorial: Table Editing

Posted by Torq Byter_ on 05 November, 2015 Read more →

TorqTune Tutorial: Live Viewing and Data Logging

Posted by Torq Byter_ on 03 November, 2015 Read more →

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