LSA - 6L90E Swap Questions

[Crackerbuzz]

Hi all,

I am installing a paired combo of a 2013 LSA 6.2 supercharged and the 6L90E tranny that came from a 2013 CTS-V.

I am also running the factory harness that we have modified, but I am still getting P0100 codes which indicate loss of communication in the CAN network, and I have successfully installed a 120 ohm resistor at the OBDII port which is now reading the correct 60 ohms across the terminals.

We are on the final streak and are looking for some knowledge advice from some of you experienced people.

Since the removal of the body module and the ABS module etc, we are wondering whether we need to be using another pair of twisted CAN wires that are connected to the transmission plug connector.

For some reason, there are 2 x sets of power/earth feeds and 3 x sets of CAN pairs within the 16 pin transmission connector.

Does anybody know what these extra feed are for and if I need to uses them now that the body/ABS modules are gone?

Do I need to swap pairs or does the transmission not too worried?

Cheers
Craig

[blindsquirrel]

How do you have the CAN wiring connected?

Do you have the original GM diagram for the CAN wiring, and a modified/edited diagram showing only the components being used in the swap? This makes things much easier.

The DLC and ECM are the ends of the CAN chain, any other modules go inline between these. Each module in the middle will have 2 sets of CAN wires.

[blindsquirrel]

The newest GM diagrams I have access to are 2009. This is a 2009 Silverado as an example.

The original diagram with a bunch of distracting garbage in it:
screenshot.21-02-2021 06.09.50.png

An edited diagram showing only what would be used for a standalone engine/trans swap:
screenshot.21-02-2021 06.09.50edited.png

[hjtrbo]

This might help you out with how the 3x power and 2x grounds to the trans should be hooked up.
1.PNG

And this is the nasty high speed canbus on a HSV 6L90 and LSA. Driveline for this car is borrowed off 2013 ZL1
2.PNG

Based on what is hanging off the high speed you will also have lots of DTC's to disable.

[hjtrbo]

This might help you out with how the 3x power and 2x grounds to the trans should be hooked up.
1.PNG

And this is the nasty high speed canbus on a HSV 6L90 and LSA. Driveline for this car is borrowed off 2013 ZL1
2.PNG

Based on what is hanging off the high speed you will also have lots of DTC's to disable.

[Crackerbuzz]

The newest GM diagrams I have access to are 2009. This is a 2009 Silverado as an example.

The original diagram with a bunch of distracting garbage in it:
screenshot.21-02-2021 06.09.50.png

An edited diagram showing only what would be used for a standalone engine/trans swap:
screenshot.21-02-2021 06.09.50edited.png

Hi Blindsquirrel...

Thanks for the reply

Here is what we have (I have added the 120 ohm resistor at the DLC and we are reading 60 ohms across pin 6 and pin 14 on the OBD2)

Is there any need to use the other pair of CAN wires or the power feeds on the tranny plug?


CAN NET.jpg

[Crackerbuzz]

This might help you out with how the 3x power and 2x grounds to the trans should be hooked up.
1.PNG

And this is the nasty high speed canbus on a HSV 6L90 and LSA. Driveline for this car is borrowed off 2013 ZL1
2.PNG

Based on what is hanging off the high speed you will also have lots of DTC's to disable.

Thanks HJ, I will look into this

[blindsquirrel]

Hi Blindsquirrel...
the other pair of CAN wires

The TCM is the thing that links the ECM to the DLC. It is a chain. There are no 'tees' allowed here.

ECM <-> TCM <-> DLC

The TCM must have a pair of CAN wires going to the ECM, and a pair of CAN wires going to the DLC. You've shown me the diagram I posted, you have not shown the diagram of how you have it connected.

Since the removal of the body module and the ABS module etc, we are wondering whether we need to be using another pair of twisted CAN wires that are connected to the transmission plug connector.

For some reason, there are 2 x sets of power/earth feeds and 3 x sets of CAN pairs within the 16 pin transmission connector.

Show me this diagram with 3 sets of CAN wires going into the TCM. Remember, there are no 'tees' allowed in the CAN wiring.

[TheMechanic]

P0100 is a MAF code. If you are getting a Uxxxx that is a communication code. You can turn them off in the PCM.

[Crackerbuzz]

P0100 is a MAF code. If you are getting a Uxxxx that is a communication code. You can turn them off in the PCM.

Sorry... I meant U0100

[Crackerbuzz]

The TCM is the thing that links the ECM to the DLC. It is a chain. There are no 'tees' allowed here.

ECM <-> TCM <-> DLC

The TCM must have a pair of CAN wires going to the ECM, and a pair of CAN wires going to the DLC. You've shown me the diagram I posted, you have not shown the diagram of how you have it connected.



Show me this diagram with 3 sets of CAN wires going into the TCM. Remember, there are no 'tees' allowed in the CAN wiring.

Thanks BS, I will come back to you on this when I get a chance.

I don't have a diagram of the transmission TECHM wiring, but there is one spare set of Can wires available on the generic plug I purchased. Not sure if this will have connections inside the T43 or if it will change the way they communicate?

This is the generic plug I purchased.

https://www.eficonnection.com/home/p...nector-pigtail

Cheers

Craig

[blindsquirrel]

You need to follow the wiring pinout for the original vehicle the ECM/TCM OS came from, as that can have an impact on the pin assignments. You need wiring diagrams.