[N Camarolina]

Thought I'd share this in hopes others have experienced, identified the cause, and are now trouble free.

Was at the track last week and went to get gas in between sessions. The concrete pad at gas station was not level, but the brakes were still hot, so when I pullled up to the pump I shut it down and left the car in gear (M6) to keep it from rolling. After gas-up was complete, I started the car (clutch in) and it started rolling backward, so I immediately let the clutch out and began rolling forward while the gauge display was going through it's "start up sequence." About 10 seconds later, the DIC goes black, the HUD disappears, and the tach and speed gauges read "0" while the vehicle is moving. I continued to drive, and the dash display would attempt to reboot itself (as when you start the car), stay on for a few seconds, then go blank again. Rinse repeat for another few minutes. I then try shutting the car off and leaving that way for a few minutes. Upon restarting, it seems like everything is normal, so I park in the paddock and await the start of the next session.

When I start the car, all seems OK. But as seen as I go out on track and get up to 80mph, the dash display goes blank again and I see some message about the key fob seat memory and another message about drive mode being changed to competitive, then DIC goes back to blank (black). Speed and tach display "0" as before. I came back into the pits, turned car off, then back on, reset drive mode to PTM, and all looks OK until I get back onto the track - then everything goes blank again.

I then packed up the car and headed home. During the 1+ hr drive home, the display was normal (worked correctly the whole time). Have driven the car three times since, with everything working normally. One of the those times I even drove on back roads in low gear at high RPM to get oil temps back up to track temp to see if hot temps could induce the problem, but to non avail.

I don't know whether this was a one-time event because of how I started driving the car right after the engine turned over (while the gauge cluster was booting up), or because I have an actual problem with the car that will need to be fixed.I've booked a diagnostic appointment at the dealer as well as looked up previous threads about this and found theories about it being anything from loose fuses in the fuse box, bad ground wire, bad ground wire connections, and even a faulty gauge cluster.

Has anyone experienced this problem with their dash display and found a dealer diagnosis that seems to have been correct?

[m6-lt1]

Yes, I had something similar happen a few years ago. We were waiting in line to go out on track. My car was off and the cars in front of me started driving. So I turned my car on and immediately started going forward as well before the gauge cluster did its thing. Had a blank screen between the gauges. I don’t remember if the gauges worked or not. That being said somewhere between 20-30 seconds it all came back on during the session and I drove during the session as normal. Never happened again.

Prior to that track day my car had the hot start issue and a week before the track day I had installed an extra thick ground wire. Originally I thought maybe that was the issue but I doubt it. I think these cars don’t like getting driven before the cluster does its thing. Keep in mind I have a 1ss non 1le (waiting for my 2ss 1le to ship )

[N Camarolina]

Thanks for the reply. It makes me feel a bit better to know that the cause might just be pulling away too soon after start-up.

It's a mystery why mine seemed to carry on after 3 engine restarts, then was fine after a cool down and fourth restart, while yours didn't even require a restart to resolve itself.

[ShockingZ]

My 21 a10 car did this after a tune flash. I had to do another tune flash (Write complete) with HPT to get it to stop doing this. I had seen a TSB somewhere on this where the dealer would reflash the computer to get it to stop. So I used my HPT setup to basically do the same and it worked. Didnt do the dash reboot thing ever again.

[Twizzty]

I have a '21 that does this randomly, three or four times a year or so. Sometimes it restarts and fixes itself and sometimes it's restarting the entire trip over and over again. Mostly happens on the street but did happen in the middle of a track day this year and that was annoying as hell! Was good to go by the next session with my normal do nothing about it solution. Maybe one day I'll get around to taking it in for the TSB on the '21's.

[N Camarolina]

Thanks Twizzty for your mention of the 2021 TSB. I found that mention on a previous thread and will bring that to the attention of the service department. I suppose it can't do any harm to reflash the software that the TSB is referring to.

Noting that yours does it randomly a few times a year is a bit disconcerting, but glad to see it clears up on its own eventually. Any chance it was caused by pulling away right after engine start, as the electronic gauges and DIC were still booting up?

[N Camarolina]

Wanted to provide an update:

Car went to the dealer, error codes said lost communication with instrument cluster. They followed the TSB and flashed the updated software. Gauges were no longer going blank (drive home from track and 7 times driving it for errands since) when I handed them the car for diagnosis, so not sure if the software update has worked or not.

Will report back if problem surfaces again.

[N Camarolina]

Final update:

The TSB software update definitely fixed the problem.

I'm now convinced the problem is caused by the car starting to move before the instrument cluster finishes booting up after the car is started. The cluster starts receiving data (from the car moving) before it's ready to receive it. After the software update, I tried again to recreate the problem. Now, under the same cause conditions, the HUD only behaves oddly for 1 or 2 seconds displaying an "[ X ]" and then goes to normal, while the instrument cluster stays lit and operative.