2002 A4 cluster doesn't turn on. Engine starts, then dies.

[xetura]

I went to start it today and noticed the cluster wasn't lighting up. No odometer or anything. Just "brake, abs and traction control" light up, nothing else. I went to start it and it starts, but then dies right afterward. I tried starting it several times and it starts every single time, just to die 1-2 seconds after it starts. It did sit for a couple days and it has been colder than normal. I can rev the motor for a second and everything sounds fine, but the engine dies shortly after. I checked all of my fuses and they're fine. I tried my spare key and it does the exact same thing. Does the engine need the cluster to start(ecu)? Luckily I have another car to drive in the meantime, but this just came out of the blue. Can the cluster just die out of the blue like this? Doesn't make any sense.

[mauromj]

Yes, without the cluster operating correctly, the car will shut itself down. This is part of the immobilizer system.

[mauromj]

I would scan for codes and report back. It sounds like you need a new cluster, but that cannot exactly be verified just yet.

[imnuts]

I'd also check the battery voltage. All sorts of funny stuff will happen if the battery is almost dead.

Sent from my Nexus 6

[xetura]

I tried jumping it with my Land Cruiser to see if the added voltage would change anything, it does the exact same thing. I'll test the battery with a multi-meter tonight just to be sure.
My abs module is bad and ever since then, VAGCOM always ends up locking up and I was told I have to fix that before it will work again. I'll see what I can do tonight.

[xetura]

Right as I got home from work, I thought I'd give it a shot. I unlocked the car, noticed the odometer wasn't turning on, but I tried it anyway. Same thing, but the battery sounded weaker this time. Sure enough, it read 11.71v at the battery. I go back in the cabin and.... the cluster is working again, reset to 2002 like the battery was disconnected!?!?!?!? WTF! Went to start it and it didn't sound right. Was almost a high pitch whining sound. It sputtered and spit, but it started. It was missing badly, but eventually stopped and ran fine like it always does. I drove it around the block and did a couple pulls once it was up to temp... it was fine. Parked it and measured the battery, 12.6v. The EPC light was on, so I ran Torque on my phone and it had p0688 and p0304. I cleared them out, started the car again, drove it around, it was fine.

Who the hell knows what happened... the only thing I can think of is the sudden cold weather screwed with my battery somehow? I did let the car sit a couple weeks back for almost a week and it was dead when I tried to start it and it had to be jumped. I've had cold start issues before, but I solved that when I replaced the cam sensor. This is new to me...

[imnuts]

Sounds like the colder weather took what life the battery had left. Do you know how old the battery is?

[xetura]

I don't. It came with the car when I bought it, roughly 3ish years ago. It's been ran dead a few times, but always seems to work once I get it charged. I'm looking at batteries now.

[xetura]

I replaced the battery. The first thing I noticed was how quickly it starts now. Usually it takes a couple seconds before it catches, but now it starts almost immediately. I also noticed the idle is now slightly higher. It was idling around 750rpm before, now it's idling at 800rpm. The interior lights are brighter now too. I took it for a drive and LOL I should of replaced it a LONG time ago. It pulls a bit harder now too lol. Yay for a new battery.

[imnuts]

Yeah, when a battery is "dead" it shortens the life of it, as does cold weather. If it repeatedly died, whatever the reason, it just makes it that much more likely to happen again. Glad it's fixed for you now though.