[Stlwaco]

I replaced the K20 PCM today do to an issue I was having. Had is factory flashed and then uploaded my tune (need this so I could start it). After all this I had three codes. One for crank position relearn, one for clutch pedal position relearn, and another for gear position sensor learn. I was able to complete the clutch pedal and crank relearns, but I'm having trouble with the gear position relearn. I can access the gear sensor position relearn in my snap on scanner and activate learn. But it is not giving me any information on what to do. Surely I don't just sit with it in neutral. I've tried rowing throw the gears KOEO but it will not complete learn. If anybody has the relearn procedure for this I would really appreciate the help.

2019 Camaro 2SS M6

-Mike

[Stlwaco]

Got it fixed. Snap on scanner is useless for this. HP Tuners has the button to begin the relearn but does not do anything once clicked. Used a factory GM scanner and it just kept failing the relearn. Finally took it to a buddy that works at a supercar shop. Used his $400 Autel. Relearn successful. No I have rev match, current gear on HUD, reverse lights and rear view camera working, not to mention that the pesky orange engine light is gone.

[Judy1le]

Originally Posted by Stlwaco

Got it fixed. Snap on scanner is useless for this. HP Tuners has the button to begin the relearn but does not do anything once clicked. Used a factory GM scanner and it just kept failing the relearn. Finally took it to a buddy that works at a supercar shop. Used his $400 Autel. Relearn successful. No I have rev match, current gear on HUD, reverse lights and rear view camera working, not to mention that the pesky orange engine light is gone.

Im having intermittent issues where my Active Rev Match will randomly not work, with no other electrical issues. I end up having to disconnect the battery and reconnect and wait for the next time it does it. Everything has pointed me towards the gear/transmission sensor. Where is it exactly? Does it need to replaced or just flashed?

[SSgtSS1LE]

Gear Position Sensor Location:



Have you pulled the diagnostic trouble codes (DTCs)? If so, what are they?

[Stlwaco]

what he said...

If the computer is disabling the Rev Match there should be a code in the system to give you an idea of what is going on. Next time pull codes. Do you have a scanner?

[Judy1le]

Originally Posted by Stlwaco

what he said...

If the computer is disabling the Rev Match there should be a code in the system to give you an idea of what is going on. Next time pull codes. Do you have a scanner?

Need to get it hooked up to HP and see what codes there are. There have not been any CELs or stabilitrack messages, so im curious if there are any codes to be seen. Thinking to start with a BCM flash and go from there.

[Stlwaco]

Doesnt matter if there is a light on or not. some codes wont set a light but will still be stored.

[Judy1le]

I looked at DTC to see if anything popped up between what I think is the diff/eLSD making a bunch of weird noises and then the ARM acting up. I have had no other issues such as the lights not working or any other electric mishaps.

The U0073 is modules not communicating which im sure is the root cause. Need to start checking wiring and fuses.

I had pulled the battery terminal the other day and im wondering if that might have cleared any codes that are not showing up.

I want to get the BCM and CCM flashed/reset but I have yet to make any phone calls yet. Maybe try that GM autox ELSD calibration.

Id like to do it myself if possible and depending on cost.

[Stlwaco]

DTC U0073 OR U2100 (DATA COMMUNICATIONS)
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach.
Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC U0073 : Control Module Communication Bus A Off

DTC U2100 : CAN Bus Communication

For symptom byte information, refer to Symptom Byte List.

Circuit/System Description
The devices connected to the high speed GMLAN serial data circuits (circuit numbers 2500 & 2501) monitor for serial data communications during normal vehicle operation. The high speed GMLAN serial data bus uses terminating resistors that are in parallel with the high speed GMLAN (+) and (−) circuits.

Conditions for Running the DTCs
Supply voltage to the devices is in the normal operating range.
The vehicle power mode requires serial data communications.
Conditions for Setting the DTC
The device setting the DTC has attempted to establish communications on the serial data circuits more than 3 times in 5 s.

Action Taken When the DTCs Sets
The device suspends all message transmission.
The device uses default values for all parameters received on the serial data circuits.
In the transmission control module, DTC U0073 will cause the transmission to go into default gears.
In the engine control module and transmission control module, DTC U0073 will cause the malfunction indicator lamp (MIL) to illuminate.
If equipped with eAssist, DTC U0073 in the hybrid powertrain control module is a type B DTC and will cause the malfunction indicator lamp to illuminate and result in the engine operating in conventional engine mode and will maintain 14 V module operation.
The device inhibits the setting of all other communication DTCs.
Conditions for Clearing the DTC
The engine control module or transmission control module turns OFF the MIL after 4 consecutive ignition cycles that the diagnostic runs and does not fail.
If equipped with eAssist, the hybrid powertrain control module turns off the MIL after the diagnostic runs and does not fail during subsequent ignition cycles. Normal operation will resume 5 s after subsequent ignition cycle.
A current DTC clears when the malfunction is no longer present.
A history DTC clears when the device ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction

Diagnosing Can Bus is a PITA. I wish you the best of luck.

[Judy1le]

Originally Posted by Stlwaco

DTC U0073 OR U2100 (DATA COMMUNICATIONS)
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach.
Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC U0073 : Control Module Communication Bus A Off

DTC U2100 : CAN Bus Communication

For symptom byte information, refer to Symptom Byte List.

Circuit/System Description
The devices connected to the high speed GMLAN serial data circuits (circuit numbers 2500 & 2501) monitor for serial data communications during normal vehicle operation. The high speed GMLAN serial data bus uses terminating resistors that are in parallel with the high speed GMLAN (+) and (−) circuits.

Conditions for Running the DTCs
Supply voltage to the devices is in the normal operating range.
The vehicle power mode requires serial data communications.
Conditions for Setting the DTC
The device setting the DTC has attempted to establish communications on the serial data circuits more than 3 times in 5 s.

Action Taken When the DTCs Sets
The device suspends all message transmission.
The device uses default values for all parameters received on the serial data circuits.
In the transmission control module, DTC U0073 will cause the transmission to go into default gears.
In the engine control module and transmission control module, DTC U0073 will cause the malfunction indicator lamp (MIL) to illuminate.
If equipped with eAssist, DTC U0073 in the hybrid powertrain control module is a type B DTC and will cause the malfunction indicator lamp to illuminate and result in the engine operating in conventional engine mode and will maintain 14 V module operation.
The device inhibits the setting of all other communication DTCs.
Conditions for Clearing the DTC
The engine control module or transmission control module turns OFF the MIL after 4 consecutive ignition cycles that the diagnostic runs and does not fail.
If equipped with eAssist, the hybrid powertrain control module turns off the MIL after the diagnostic runs and does not fail during subsequent ignition cycles. Normal operation will resume 5 s after subsequent ignition cycle.
A current DTC clears when the malfunction is no longer present.
A history DTC clears when the device ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction

Diagnosing Can Bus is a PITA. I wish you the best of luck.

Wishful thinking is that since my lights, dashboard, among other electrical components, are not going haywire, its an “isolated” thing and hopefully I can find it somewhere somehow. Ive seen other reports of camaros and corvettes having issues with their ARM similar to my case, I just cant find the “fix” for it searching online.

The issue only arises intermittently and is not a constant and removing the neg terminal for a soft reset, resolves it. Its got to be something silly. I figured if there was any wiring or fuse issues, it would be more of a constant issue

[Stlwaco]

it could be something as simple as pin tension. pretty common on these newer gm vehicles since they use tiny terminals.




#PIT5074M: J-35616-64B OR EL-35616-58 TERMINAL TEST PROBE INFORMATION/REPAIR (NOV 5, 2019)
Subject: J-35616-64B Or EL-35616-58 Terminal Test Probe Information/Repair


Brand:

Model:

Model Year:

VIN:

Engine:

Transmission:

from

to

from

to

All

All

2005-2020

All

All

All

All


Supersession Statement
This PI was superseded to update Model Years. Please discard PIT5074L.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Recommendation/Instructions
When diagnosing an intermittent electrical concern terminal tension is one of the main culprits, especially when working with very small terminals. More and more modules and inline connectors are using small .64 series terminals, also more modules are beginning to use the Mini 50 series terminals. When checking terminal tension it is important to use the correct test probe. The J-35616-64B is the latest test probe released for checking tension or probing the .64 series terminals. Also the EL-35616-58 is the latest test probe released for checking terminal tension on the Mini .50 series terminals. See pics below.

Note:Always refer to the Connector End View in Service Information for the latest information on determining the correct test probe to use.

Information on 64 series terminals
If the terminal end of the J-35616-64B is bent, damaged, worn or broken, it should not be used and a replacement test probe or terminal should be obtained from GM Tools at 1-800-468-6657. The test probe terminal has been released in the terminal repair kit (J-38125-620H) located in Lear Tray 7 part number 963716-2 shown below. (Note: When calling Kent-Moore to order terminal 963716-2, the actual part number is 963716-2PKG since they are only sold as a pack) This terminal may also be used to make jumper wires; example: to jumper the High Speed LAN circuits together in order to bypass a module for testing only. Use crimping tool J-38125-641 and jaw "H" for 22ga wire, "J" for 20 ga wire, or "K" for 18 ga.

If you cannot locate the Terminals in your terminal kit "Tray 7" your kit is not up to date, and Kent tools will need to be contacted so your kit can be updated.

Another option is to order the .64 test probe terminal already connected to a lead/wire called a terminated lead. The GM part number is 13505346, which can be ordered through your normal GM CCA parts channel. There are 5 terminated leads in a package, shown below. With the addition of this new terminated lead, there are now 3 different options for obtaining the proper .64 test probe/terminal:

.64 Test Probe - J-35616-64B (ordered from GM Tools at 1-800-468-6657)
.64 Replacement Terminal - Lear Tray 7 part number 963716-2 (ordered from GM Tools at 1-800-468-6657)
.64 Terminated Lead - GM part number 13505346 (ordered from GM CCA parts)

[Judy1le]

Originally Posted by Stlwaco

it could be something as simple as pin tension. pretty common on these newer gm vehicles since they use tiny terminals.




#PIT5074M: J-35616-64B OR EL-35616-58 TERMINAL TEST PROBE INFORMATION/REPAIR (NOV 5, 2019)
Subject: J-35616-64B Or EL-35616-58 Terminal Test Probe Information/Repair


Brand:

Model:

Model Year:

VIN:

Engine:

Transmission:

from

to

from

to

All

All

2005-2020

All

All

All

All


Supersession Statement
This PI was superseded to update Model Years. Please discard PIT5074L.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Recommendation/Instructions
When diagnosing an intermittent electrical concern terminal tension is one of the main culprits, especially when working with very small terminals. More and more modules and inline connectors are using small .64 series terminals, also more modules are beginning to use the Mini 50 series terminals. When checking terminal tension it is important to use the correct test probe. The J-35616-64B is the latest test probe released for checking tension or probing the .64 series terminals. Also the EL-35616-58 is the latest test probe released for checking terminal tension on the Mini .50 series terminals. See pics below.

Note:Always refer to the Connector End View in Service Information for the latest information on determining the correct test probe to use.

Information on 64 series terminals
If the terminal end of the J-35616-64B is bent, damaged, worn or broken, it should not be used and a replacement test probe or terminal should be obtained from GM Tools at 1-800-468-6657. The test probe terminal has been released in the terminal repair kit (J-38125-620H) located in Lear Tray 7 part number 963716-2 shown below. (Note: When calling Kent-Moore to order terminal 963716-2, the actual part number is 963716-2PKG since they are only sold as a pack) This terminal may also be used to make jumper wires; example: to jumper the High Speed LAN circuits together in order to bypass a module for testing only. Use crimping tool J-38125-641 and jaw "H" for 22ga wire, "J" for 20 ga wire, or "K" for 18 ga.

If you cannot locate the Terminals in your terminal kit "Tray 7" your kit is not up to date, and Kent tools will need to be contacted so your kit can be updated.

Another option is to order the .64 test probe terminal already connected to a lead/wire called a terminated lead. The GM part number is 13505346, which can be ordered through your normal GM CCA parts channel. There are 5 terminated leads in a package, shown below. With the addition of this new terminated lead, there are now 3 different options for obtaining the proper .64 test probe/terminal:

.64 Test Probe - J-35616-64B (ordered from GM Tools at 1-800-468-6657)
.64 Replacement Terminal - Lear Tray 7 part number 963716-2 (ordered from GM Tools at 1-800-468-6657)
.64 Terminated Lead - GM part number 13505346 (ordered from GM CCA parts)

Where are these terminals/pins located?

[Stlwaco]

on the modules and connectors

[Judy1le]

Originally Posted by Stlwaco

on the modules and connectors

Youve been superful helpful and I certainly appreciate your responses and efforts. Ill do my best at trying to trouble shoot this and try to remember to post it up/update for the next person.

For shits and gigs I checked both fuse boxes. Had some the seemed like they damn near popped out and had to be depressed back into place. Car is modified and there is a bit of NHV back there. Highly doubt this is the culprit but ill continue to monitor and work my way through it.