Oh Oh..

[Jono5900]

2012 S5 Convertible with very low mileage(40k) and I thought I'd post this if anyone knows of this issue.

Chronology:

A few months ago while looking in the trunk, I see a bone colored handle on the underside of the hood and being the cautious measured guy that I am, I pulled it..well nothing happened as I discovered later that it's a way for someone to exit the trunk if "stuck" inside..and I wasn't

I don't know if it's coincidence but like 30 minutes later I'm driving down the avenue with the top down and all of a sudden the dashboard goes blank(eerie not seeing anything in the box between the Tach & Speedometer), a warning tone comes on, the AIR BAG & Electric Stability warning lights illuminate in the Tach and the ABS & BRAKE warning lights in the Speedometer. Car still runs but there's clearly something wrong. I pull over and thought it best to raise the top but that's not working(the car is still running). I turn off the engine for 10 minutes and start it up again and within 20 minutes it happens again..eventually I park it in front of my building with plans to drop it off at the shop first thing in the morning. The next day I reluctantly start the car up and head toward the shop and it was as if nothing happened..wow, prob just a fluke I'm thinking or hey maybe I did something while pulling down on that handle.

Results from the shop was diagnostic scan was completely normal..of course it was..

They suggested that next time I bring it in while it's happening..Ok, give me a minute to discuss this with my car to make sure we're on the same page on this

No issues for the following 2 months and then today when far from home, it happened again twice..each time I freaked out(of course in gridlocked traffic).

What I can say for sure is I believe the top was down for all occurrences

I'll be providing shop with this new info as first time I was caught off guard but today I took a video of the dash and warning lights while it was going down.

Anyone ever hear of such a thing?

TIA

[Mrads]

When it happened to my S5 it was faulty power relays

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[Smac770]

underside of the "rear lid" or "trunk lid", not "hood" or "bonnet". Yes, emergency release handle, it's just cabled to the latch and does not toggle any state change related to the car electronics.

This is why people should own their own scan tools. You need to scan for codes while the ignition is still on when the event occurred. Lot of stuff self clears on ignition off (eg engine off).

So while the DIS (driver information screen, on the instrument cluster) went blank, the speedo and tach still were lit and reporting values as expected?

Sounds like something starting to flake out, but not nearly enough problem isolation to say what.

[Jono5900]

When it happened to my S5 it was faulty power relays

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Appreciate the input..will explore further..

[Jono5900]

Good question..So it looks like speedo and tach weren't lit..just the light emanating from the 4 warning ligts.

I've uploaded the video after pulling into the lot. I guess disregard the second half of clip as I turned engine off and back on so I could put the top up.

[Smac770]

Backlighting was out, but the gauges were working. You might have something breaking down in the instrument cluster? Scan for DTCs with VCDS really would be the important next step. Are you looking at some internal fault isolated to just the J285 instrument cluster, or is more of the car having issues too. And is the J285 aware it's malfunctioning, or is it just unmonitored circuits failing.

[Jono5900]

Backlighting was out, but the gauges were working. You might have something breaking down in the instrument cluster? Scan for DTCs with VCDS really would be the important next step. Are you looking at some internal fault isolated to just the J285 instrument cluster, or is more of the car having issues too. And is the J285 aware it's malfunctioning, or is it just unmonitored circuits failing.

Thanks again for the input. I do have the Launch Creader 3001 obd2 scanner which I bought when I got the car..prob only used it once. Will get comfortable with it again by doing some regular scans while the car is operating normally and keep it nearby for the next time it happens

Sent my Audi guy the video and once again he responded "We need to scan when you're actually having the issue"

Hopefully, codes will appear when it happens next and I'll be able to convey them to everyone..including this thread.

As far as the "Are you looking at some internal fault isolated to just the J285 instrument cluster, or is more of the car having issues too. And is the J285 aware it's malfunctioning, or is it just unmonitored circuits failing" question I don't know what any of that is..I will say I have 2 additional issues going on, now that I think of it.

1- After parking on even the slightest incline, when I restart the car, sometimes the fuel meter doesn't work and the needle sits at the bottom of gauge. However, once I'm driving a bit and eventually look at it again, it's always back to working correctly..sensor?

2- I've also noticed that after not having driven it for a week or so, when I approach the car with the Fob in my pocket, it no longer recognizes it. I have to press the unlock button on the Fob. However, if I use the car and turn it off for a short period of time(like when out shopping) and I return to the car, it recognizes it and does that double chirp sound and I can open the door w/o taking the Fob out..coincidentally this is a newish issue.

Not sure if these two are related to what's going on...

Thanks again...

[Smac770]

I'll say good luck with that tool, VCDS is the de facto standard, and anything that's not it is not as good as it for the purpose at hand (unless you have actual ODIS).

J285 refers to the instrument cluster module, all electrical things in the car are identified by some identifier. The instrument cluster unit is the J285. It has a connector plug. Either the issues are inside the J285, maybe with flaky connection at the connector plug, or outside the J285. The fuel level sensors are directly wired to the J285, the value is not coming in over some digital communications bus (CAN, LIN, etc). It might be the sensor, the wiring, or the J285. The sensor can be checked at the in-tank fuel pump flange. Might be the connector at that end, but given all the issues with the J285, probably just your J285 flaking out.

2 sounds like the situation where the J393 sleeps the keyless sensors, maybe a low voltage thing. I had the same problem when my door handle sensor was going bad. But that's where a full VCDS autoscan comes in.

[Jono5900]

I'll say good luck with that tool, VCDS is the de facto standard, and anything that's not it is not as good as it for the purpose at hand (unless you have actual ODIS).

J285 refers to the instrument cluster module, all electrical things in the car are identified by some identifier. The instrument cluster unit is the J285. It has a connector plug. Either the issues are inside the J285, maybe with flaky connection at the connector plug, or outside the J285. The fuel level sensors are directly wired to the J285, the value is not coming in over some digital communications bus (CAN, LIN, etc). It might be the sensor, the wiring, or the J285. The sensor can be checked at the in-tank fuel pump flange. Might be the connector at that end, but given all the issues with the J285, probably just your J285 flaking out.

2 sounds like the situation where the J393 sleeps the keyless sensors, maybe a low voltage thing. I had the same problem when my door handle sensor was going bad. But that's where a full VCDS autoscan comes in.

Thanks so much for your input as I'm in a better place now with these issues than I was before..Really appreciate it

[Jono5900]

Forgot to update this issue..which fortunately seems to be resolved. So, after getting nowhere with my Audi garage I tried another Audi repair place. Net net, they replaced my alternator and gave me a new battery and everything seems to be working fine. So, if anyone with a S5 Cab encounters an issue like documented in my initial entry, it could be your alternator. Why my default garage couldn't figure this out or even consider it, instead charging(pun intended) me for an expensive scan that yielded "everything checked out" result. How do you not check such an important part of the charging system is beyond me. Anyway, I now have a new repair shop and thanks to all that weighed in with input