[2SS Capt]

Code P0700 / U0100 (2020 2SS, A10)

Went to lunch with my daughter today, car ran fine, shut it down to eat and got in and started it up and the only gauge that worked was the Volts meter, everything else showed 0 and the Check Engine light was on, shut it down twice and tried a restart same thing.

Drove home slowly (6 miles), transmission wouldn't shift and car sounded weird (very deep), thinking it was in 2nd or 3rd gear as it kind of lugged and the tone was very strange...

Got it home and plugged in my OBD-II reader and got the following codes:

P0700
P26C8
U0100
U0100

I cleared the codes and started the car, everything is back to normal, took it for a drive and everything seems fine.

So, one time fluke or is something going bad? Car has 10.5 months old and has 2,900 miles on it and is stock (except for a GMP CAI (with the associated GM tune) and a Mishimoto Catch Can)...

Is there a TCM or ECM update I should go to the dealer to get done? Should I wait to see if it does it again?

Any input would be greatly appreciated!

[Bolzy]

Curious to know if you unplugged the Range disabler unit while experiencing the issue...maybe some correlation??

Obviously to read/clear codes, you had to...

[cam765]

Interesting. Take a look at TSB #20-NA-055. (This TSB was expanded to include more models including 2018-2020 Camaro SS and ZL1). There appears to be two fault conditions that are most commonly mentioned:

1. Aborted Crank:
Vehicle begins to crank, stops cranking and then has a successful start

2. CAN Lockup:
IPC gauges inoperative
Numerous DIC error messages
Oil pressure gauge reads zero
Coolant temperature gauge reads zero
Speedometer gauge reads zero
Tachometer gauge reads zero
Fuel gauge reads zero
Engine appears to be operating in a reduce power mode
No brake assist
Possible no electric power steering assist
Transmission in default gear
Battery gauges are correct
No reverse gear and/or no back-up lights
DRL inoperative
Numerous DIC error messages displayed
Note: Headlights can be manually turned On

Note: U0100 alone is not a good indication of this issue. A better indication of the condition are the symptoms listed above.

So, as it sounds like the transmission being in a default gear, multiple gauges not working, and the battery gauge working, this may describe your problem. Looks like the cause is a software anomaly and the fix is to program the ECM to the latest software update. Not sure if you can just mention this to the dealer and that will be enough to get the software update or if you just need to watch out for if it happens again.

[2SS Capt]

Originally Posted by cam765

Interesting. Take a look at TSB #20-NA-055. (This TSB was expanded to include more models including 2018-2020 Camaro SS and ZL1). There appears to be two fault conditions that are most commonly mentioned:

1. Aborted Crank:
Vehicle begins to crank, stops cranking and then has a successful start

2. CAN Lockup:
IPC gauges inoperative
Numerous DIC error messages
Oil pressure gauge reads zero
Coolant temperature gauge reads zero
Speedometer gauge reads zero
Tachometer gauge reads zero
Fuel gauge reads zero
Engine appears to be operating in a reduce power mode
No brake assist
Possible no electric power steering assist
Transmission in default gear
Battery gauges are correct
No reverse gear and/or no back-up lights
DRL inoperative
Numerous DIC error messages displayed
Note: Headlights can be manually turned On

Note: U0100 alone is not a good indication of this issue. A better indication of the condition are the symptoms listed above.

So, as it sounds like the transmission being in a default gear, multiple gauges not working, and the battery gauge working, this may describe your problem. Looks like the cause is a software anomaly and the fix is to program the ECM to the latest software update. Not sure if you can just mention this to the dealer and that will be enough to get the software update or if you just need to watch out for if it happens again.

AWESOME!!! Thank you very much, that is exactly what happen, every detail you mentions was exactly what I experienced.

I'll have to make an appointment with my dealer and have them flash the ECM to the latest software.

THANK YOU!

[2SS Capt]

Originally Posted by cam765

Interesting. Take a look at TSB #20-NA-055. (This TSB was expanded to include more models including 2018-2020 Camaro SS and ZL1). There appears to be two fault conditions that are most commonly mentioned:

1. Aborted Crank:
Vehicle begins to crank, stops cranking and then has a successful start

2. CAN Lockup:
IPC gauges inoperative
Numerous DIC error messages
Oil pressure gauge reads zero
Coolant temperature gauge reads zero
Speedometer gauge reads zero
Tachometer gauge reads zero
Fuel gauge reads zero
Engine appears to be operating in a reduce power mode
No brake assist
Possible no electric power steering assist
Transmission in default gear
Battery gauges are correct
No reverse gear and/or no back-up lights
DRL inoperative
Numerous DIC error messages displayed
Note: Headlights can be manually turned On

Note: U0100 alone is not a good indication of this issue. A better indication of the condition are the symptoms listed above.

So, as it sounds like the transmission being in a default gear, multiple gauges not working, and the battery gauge working, this may describe your problem. Looks like the cause is a software anomaly and the fix is to program the ECM to the latest software update. Not sure if you can just mention this to the dealer and that will be enough to get the software update or if you just need to watch out for if it happens again.

Do you have the expanded TSC as the one posted doesn't include the Camaro's...

[cam765]

Originally Posted by 2SS Capt

Do you have the expanded TSC as the one posted doesn't include the Camaro's...

Here is the updated one.

[2SS Capt]

Originally Posted by cam765

Here is the updated one.

Excellent!!!

THANK YOU!!!

[cam765]

Originally Posted by 2SS Capt

Excellent!!!

THANK YOU!!!

No problem, hopefully that resolves the issue!

[2SS Capt]

Originally Posted by cam765

No problem, hopefully that resolves the issue!

I have an appointment at the dealer on Thursday to get the ECM flashed with the latest software. That SB describes my issue completely.

The dealer wasn't happy I cleared the codes (I had to, the car was barely drivable) but they are going to flash it for me regardless.

Thanks Again!

[2SS Capt]

Went to the dealer and had TSB 20-NA-055 (v1.6) completed (reflash of the ECM)... Hopefully this problem will never recur...

Here is the TSB: TSB 20-NA-055 (v1.6 - Sept 2020)

Because when you are going roughly 30 mph your instrument cluster shouldn't look like this (issue happened at start up but I had to get it home (about 4 miles), my daughter took this while I was driving):



Car wouldn't shift, stayed in one "default" gear which I think was 2nd or maybe 3rd, sounded weird, check engine light on and Traction Control light on... Glad to find out it was a known issue and there was a fix for it (the above TSB).

[cam765]

Good follow up! This will help anyone else tremendously if their Camaro has the same issue.

[2SS Capt]

Originally Posted by cam765

Good follow up! This will help anyone else tremendously if their Camaro has the same issue.

Thanks, I freaked out when it happened to me and was VERY concerned it would be a very difficult to find, intermittent issue (and I lost faith in driving the car long distances), I was thrilled to find out it was a known issue AND there was a fix for it, thanks to this forum!

[Dexterpoole2014]

Originally Posted by 2SS Capt

Thanks, I freaked out when it happened to me and was VERY concerned it would be a very difficult to find, intermittent issue (and I lost faith in driving the car long distances), I was thrilled to find out it was a known issue AND there was a fix for it, thanks to this forum!

hello, so i am also having those same exact issues that are in the TSB on my 2018 zl1. Thankfully i found this forum and im going to have them look at this TSB tomorrow.

[2SS Capt]

Originally Posted by Dexterpoole2014

hello, so i am also having those same exact issues that are in the TSB on my 2018 zl1. Thankfully i found this forum and im going to have them look at this TSB tomorrow.

Good luck! Glad to help!

Knock on wood, I have not had a single issue since the ECM flash was completed (per the TSB)...