GM Issues Fix For C8 Corvette Transmission Control Module Communication Loss7
General Motors has issued a service update to address a problem related to the Transmission Control Module in certain examples of the 2020 and 2021 model-year C8 Corvette Stingray.
The problem: in affected vehicles, the Transmission Control Module (TCM), after detecting a loss of communications, may incorrectly clear the “loss of communications” Diagnostic Trouble Codes upon switch off. If the loss of communication with the TCM persists, the vehicle may not detect it again when the vehicle is turned back on. If this were to happen, the transmission could operate in a default mode with no Diagnostic Trouble Codes reported and the Malfunction Indicator Light not illuminated.
The hazards: while this issue does not pose a safety hazard, it could prevent the vehicle’s transmission from performing as intended and should thus be addressed as soon as possible. This problem could also prevent the transmission from producing DTCs or an MIL if something more serious were wrong with the unit.
The fix: this problem can be remedied via an over-the-air software update. Owners can also have their vehicle serviced at a GM dealer to receive the software updates, although installing them on the vehicle’s touchscreen is a fairly straightforward process.
Affected components: Transmission Control Module (TCM).
Owners should: Owners can accept the terms and conditions for over-the-air software updates in their vehicle’s touchscreen and perform the update themselves, or take the vehicle to a dealer for service. Owners with questions or concerns regarding this service bulletin can also reach out to GM using the contact information provided below.
- General Motors Service Update Number: 212336960
- Chevrolet Customer Service: 1-800-630-2438
- NHTSA Toll Free: 1-888-327-4236
- NHTSA (TTY): 1-800-424-9153
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“This problem can be remedied via an over-the-air software update.”
Another point in my favor here. I was told incorrectly that the C8 couldn’t do this type of update. I rightly told them it could.
To the Author and/or Editor: The picture of the white corvette (last one in the post) is a 2022, but this story is only for 2020 and 2021 model years. I don’t care but I know how corvette customers are, lol.
If only they could issue a recall for lack of a third pedal.
Interesting article. I did get an over the air update but still had to have my transmission replaced by GM in my 2021 C8 after multiple alarms and trying several things. First they replaced the valve body which took several weeks to get then later the entire transmission. at about the 4000 mile mark.
What about the other 9 issues this plastic piece of junk has LOL.
2021 C8 in for the second time for transmission service 9,000 mi (P0806) Chevrolet wants valve replaced before replacing transmission. Should I expect some kind of compensation from GM ie free extended warranty?
Sure Fixes for Defective Corvettes: 1) Return it to the dealer and sue to get your money back. 2) Make sure it’s fully insured, go get 5 gallons of gas for the lawn mower, oh no the gas spilled out and the car burns to the ground…. oh how terrible.. Okay, maybe that’s not the solution you want… because it’s so pretty.
GM is trying it’s best to convince everyone that Ford isn’t the only ones who can built crappy transmissions…. Who was low bid on this special limp mode 8 speed? Well it’s clearly NOT a software glitch that’s causing all that fluid to pool under that new Vette in your air conditioned garage. Loyal customers paid $65K to $85K for a Chevy Corvette and the transmissions fail or start leaking before 10,000 miles. That’s just plain sad. They’re so pretty, but just don’t try and drive them. Yeah, maybe you should have ponied up and just bought a Acura NSX…