Why The C8 Corvette May Display A Service Transmission Message23
GM has found the root cause of the transmission problems experienced by some C8 Corvette owners that can result in a ‘Service Transmission’ message appearing on the Driver Information Center (DIC).
According to a recent post on the GM TechLink site, some 2020 to 2022 model year C8 Corvette owners may observe a ‘Service Transmission’ message on the DIC, along with an illuminated Check Engine light and a squealing sound immediately after starting the engine. Error codes may also be stored in the Engine Control Module (ECM) and Transmission Control Module (TCM) indicating there is a problem with these systems.
GM says that these problems are default actions of the vehicle when the TCM is in a defaulted state. When this happens, the TCM may not be properly controlling the pressure in the transmission line, resulting in the transmission operating at maximum line pressure. A permanent fix for this problem is not available at this time, although GM TechLink says the condition “should be resolved by allowing the vehicle to go through a complete sleep cycle (i.e., 15 minutes).” The site also suggests technicians “explain to customers that they can complete this process if they experience the condition again before a correction is available.”
GM pushed an over-the-air software update to certain C8 Corvette models last November to address a problem related to those vehicles’ TCM. The automaker also launched an investigation into certain Corvette C8 transmissions last year after receiving reports that some owners had experienced gasket failures. It does not appear as though this line pressure problem is related to either of those issues.
GM says permanent repair information for owners experiencing the line pressure problem described in this article “will be released when available.”
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My dad told me, NEVER buy first year of a new American vehicle.
I agree to not get first year models, used or new. But in the case of this monumental release, the theory was Chevy’s reputation and success were at stake. I felt confident the 2020 would be a winner. And the 2021 was the exact same car, except for included Carplay, a software feature. These are great cars, at MSRP, not at inflated markups.
Well if you used that advice on a C7 with automatic transmission it wouldn’t have done you any good. The C7’s had issues with their A8 transmissions from the first model year 2014 right up until their last year 2019.
I think the 14 corvette had the 6spd auto in it , not the 8spd .
A manual transmission on a C7 solves that problem.
Not the 2014 as they were still using the tried and tested A6 but when they went to the A8 in 2015 issues arose.
My 2020 HTC has been flawless, but I did buy the extended warranty, so Murphy’s law is playing out….
Unfortunately this issue is for “some 2020 to 2022” C8 Corvettes. So not buying the first year wouldn’t have made a difference.
How are 2023 models immune? What changes have been made?
Unrelated to the issue but I wonder why GM no longer offer Morrello Red Interior. It seems to appear in many photos, like the one in this article.
Because what they offer is tied to order rate history. If something isn’t ordered enough to maintain the option it gets cancelled.
agreed, funny though, my first order for a 2020 morello red, was canceled, then i switched to adrenaline red and got delivery of a 2021. one less morello…
my 2021 goes into limp mode and throws a light, then it goes away. the code says it is a solenoid or valve ( can’t remember), but i learned not to worry . i thought it might be small manufacturing debris, but maybe not after reading this.
still the most fantastic piece of machinery i have ever owned. i love this car.
10,000 miles plus.
Wen will the z51 package be available again on 2023 production thanks,
GM should recall the C 8 or extend the warranty for all while they come up with a fix for the transmission problems
There are a number of us that have had our cars for a year and a half or two years but with very little mileage
Will this problems show up when we hit a certain number of miles and our warranty is already expired ?
>> extend the warranty for all while they come up with a fix
This is why the warranty period has an ending in the first place. They don’t want to have to pay to fix it, obviously.
For the love of God GM, get a backbone admit to the problem out loud and fix it. Your going to destroy a good car with a horrid reputation.
gmarcucio: The 2014 C7 did NOT have the transmission/torque convertor problems of the 2015-2019 models. The 2014 C7 featured the same 6 speed automation transmission that was used in the C6 models. The 8 speed automatic transmission was not introduced until the release of the 2015 C7 model year.
Another OTA Update I didn’t get
My 2021 C8 had the transmission replaced by dealer at 1240 miles. Hope they find a permanent fix. I doubt the replacement transmission is any different from the original.
I have a cheap 2016 Japanese car with almost 100k miles. The transmission doesn’t leak, and neither does anything else. It’s the most amazing thing
Any updates on this ? Mine just got the transmission problem, check engine light turned on. You can read the messages: “service transmission” and “idle creep temporarily disabled” also, if you scan the car codes you get the following:
P0700: Transmission Control System
P2714: Pressure Control Solenoid D Performance/ Stuck Off
P0849: Transmission Fluid Pressure Sensor/Switch B Circuit Intermittent
Insane, I did there OTA update last week and then I don’t have even gear numbers. Has anyone gone through this and resolved it?