[Shenron]

Hello everyone, we had to replace the motor in my 2016 camaro v6, we bought an engine out of a 2017 camaro v6 but one of the engine harness wires were broke so we swapped my original wiring harness off the engine we took out of my car to the 2017 motor, everything matched up and looked good, long story short. When i press the start button it says ‘shift to park’ and there is no gear indicator of what gear i’m in, we had a buddy come over with a solus pro and try to scan for engine codes, both the tcm and the ecm wont respond, the BCM does. We checked grounds and everything seems to look good, no wires seem to be lose and everything seems to be in the correct place, does anyone have any ideas?

[Need4Camaro]

Did you reuse your original ECM, TCM and BCM? You can't interchange those between cars.

[Shenron]

Originally Posted by Need4Camaro

Did you reuse your original ECM, TCM and BCM? You can't interchange those between cars.

Yes sir! Same ecm bcm and tcm, we never touched them

[TP2SS]

You might try swapping all the sensors off your original engine onto the new one. Could be a bad sensor on the new engine that isn’t playing nice. Sounds like it’s more of a trans sensor, though.

[Shenron]

Originally Posted by TP2SS

You might try swapping all the sensors off your original engine onto the new one. Could be a bad sensor on the new engine that isn’t playing nice. Sounds like it’s more of a trans sensor, though.

Hey! Thanks for the information, We were also thinking this, however. We can’t find a diagram for any of the sensors, or which sensor may power the ecm/tcm or anything like that, any ideas on which sensors we should switch? I am aware of the camahaft sensors on the front of the engine etc, nothing else though.

[dmcmahan60]

Could it be this?
https://www.camaro6.com/forums/showt...ght=shift+park

[TP2SS]

Originally Posted by Shenron

Hey! Thanks for the information, We were also thinking this, however. We can’t find a diagram for any of the sensors, or which sensor may power the ecm/tcm or anything like that, any ideas on which sensors we should switch? I am aware of the camahaft sensors on the front of the engine etc, nothing else though.

Anything the engine harness is plugged into on the engine/trans, with the exception of the injectors I'd guess. Anything that is "plugged in" is likely some type of sensor/sender.

[Shenron]

Originally Posted by dmcmahan60

Could it be this?
https://www.camaro6.com/forums/showt...ght=shift+park

I don’t personally think so, because the ecm and tcm wont respond to code readers, flashing or anything.

[cam765]

Does the scan tool communicate with the Power Steering Control Module or the Electronic Brake Control Module? If so, you may have isolated your issue to the TCM. The high speed CAN is daisy chained in this order: ECM -> TCM -> PSCM -> EBCM ... Your point about seeing no gear indication leads me to think this is the problem.

I would take a real good look at the connection going to the TCM and the TCM itself. If you still can't see anything wrong, you could disconnect the TCM and jumper wire the CAN pins themselves in the connector to allow communication with the ECM. Your TCM won't be happy obviously as it is disconnected, and I am unsure if you will be able to start the car since it won't know what gear the trans is in, but you will be able to get the ECM talking to the scan tool at least.

[Shenron]

Originally Posted by cam765

Does the scan tool communicate with the Power Steering Control Module or the Electronic Brake Control Module? If so, you may have isolated your issue to the TCM. The high speed CAN is daisy chained in this order: ECM -> TCM -> PSCM -> EBCM ... Your point about seeing no gear indication leads me to think this is the problem.

I would take a real good look at the connection going to the TCM and the TCM itself. If you still can't see anything wrong, you could disconnect the TCM and jumper wire the CAN pins themselves in the connector to allow communication with the ECM. Your TCM won't be happy obviously as it is disconnected, and I am unsure if you will be able to start the car since it won't know what gear the trans is in, but you will be able to get the ECM talking to the scan tool at least.

It connects to everything but the ecm and tcm.

Edit: i am not sure if it connects to the PSCM, the steering wheel does not lock like it usually does.

[cam765]

Originally Posted by Shenron

It connects to everything but the ecm and tcm.

Edit: i am not sure if it connects to the PSCM, the steering wheel does not lock like it usually does.

If it is convenient, I would try the scan tool again and just try to establish communication with the PSCM. If you have good comms, then at least you've narrowed the possibilities down to whatever comes before the PSCM (the TCM).

[cam765]

Do you also notice a gas gauge reading of zero on the cluster? I bet you have a "simple" wiring mistake going on. Maybe a connector is somehow installed flipped around or something.

If you want to probe around the TCM connector, you can see if CAN is active at the TCM.

- Pin 37 (blue): high speed GMLAN (+) to PSCM
- Pin 38 (white): high speed GMLAN (-) to PSCM

- Pin 53 (blue): high speed GMLAN (+) to ECM
- Pin 54 (white): high speed GMLAN (-) to ECM

So a check you could do would be to disconnect the TCM, and place a jumper wire between pins 37 & 53 (blues) and another jumper wire between pins 38 and 54 (whites). Be careful when inserting jumper wires into the connector, you do not want to "spread" the receiving terminals too far apart. If this brings back communication, you for sure have something weird going on at the TCM.

[Shenron]

Originally Posted by cam765

Do you also notice a gas gauge reading of zero on the cluster? I bet you have a "simple" wiring mistake going on. Maybe a connector is somehow installed flipped around or something.

If you want to probe around the TCM connector, you can see if CAN is active at the TCM.

- Pin 37 (blue): high speed GMLAN (+) to PSCM
- Pin 38 (white): high speed GMLAN (-) to PSCM

- Pin 53 (blue): high speed GMLAN (+) to ECM
- Pin 54 (white): high speed GMLAN (-) to ECM

So a check you could do would be to disconnect the TCM, and place a jumper wire between pins 37 & 53 (blues) and another jumper wire between pins 38 and 54 (whites). Be careful when inserting jumper wires into the connector, you do not want to "spread" the receiving terminals too far apart. If this brings back communication, you for sure have something weird going on at the TCM.

Attachment 1096771

Attachment 1096772

My gas gauge reads that it is empty.

[cam765]

Originally Posted by Shenron

My gas gauge reads that it is empty.

Well, I think you got TCM stuff to look at, I'm pretty confident.