Hi, A friend has a 2010 A4 that has just been serviced and MoT. It drove back fine, parked up, and locked using the remote. All fine. Two days later she says that it won't unlock using the remotes, the flashing LED on the driver's door isn't flashing, and some dashboard lights are on. She has not opened it using the key. Any ideas what migth've happened before I go over and take a look? Ta.
Audi A4 seems a bit dead!
Feb 10, 2023
Last reply: 3 years ago
67 Replies
Not really, I had a 2011 A4, don't think I ever noticed any lights remain on the dash once the key was pulled out of the 'pocket' on the dash, I'd expect the alarm to sound when the key is used in the door, if it won't shut up the battery is under spare tyre in boot ...
Two thoughts, is there a radio ham or radio station nearby. Failing that does the remote actually wok, ie is the battery flat, or maybe somebody tried to hack into it. As these clever systems age they can and do give rise to some bizarre faults. Might be worth calling back the place that did the work on it. Brian
Thanks. I managed to get in using the key, no alarm. Dashboard lights very dim. I got into the back to release the boot and put the battery on charge. My charger seems to indicate that the battery was completely flat. Now the alarm's gone off! Disconnect battery terminal to leave it independently on charge, alarm still sounded for about 10, minutes. So now we don't know why the battery went flat.
Ta. Battery is flat. Now we need to find out why.
left something on battery stone dead can you not open it with a key?
Yes. See earlier replies. Opened with the key and battery is now on charge. Nothing obvious that caused battery to drain.
A little extra info. She drove the car back from MoT/service on Tuesday at about 2:50pm. There is CCTV of the little alarm LED flashing by the driver's window, but this stops at 8:00pm. So in those 5 hours the battery died. No lights were left on.
It could just be co-incidence.
Some years ago, on New Years eve, while visiting Ireland, we started the car with no problem, drove about 5 miles, parked up to look out over a stormy see for 15 minutes and came back to a totally dead battery. Down to 8.6 volts. No signs of imminent failure, it just died.
Luckily we managed to get a number for someone who came and jump started it, which got us back to our accomodation and he brought a new battery round the next morning.
How does a battery just die?
It's often a complete mystery.
Twice I've had to rescue my wife after she'd been to a supermarket, and wanted to come home. The first time was in a Metro, and (as expected) a couple of minutes with my jumper leads got her started.
However, second time, in a Citroen C1, I had great difficulty getting enough charge in the battery for the engine to even think about starting. [Unfortunately, I didn't have my multimeter this time, so I don't know how low it was.] Eventually the engine caught, and my wife got home OK (with me following) - and I went straight to Halfords for a new battery.
Surprisingly, I subsequently couldn't find anything obviously wrong with the duff battery, so I started using it for other purposes. However, after a few weeks it suddenly died again, so I guess that there probably was an internal partial open circuit.
the garage haven't left an OBD dongle plugged in, sucking power?
Battery has partially died.
Something left on, a short, or just an old battery that died anyway. Take it to a place to get battery tested. after fully charging it.
If it is suspect change it. Dead batteries apparently account for 50% of all AA callouts
Sometimes whiskers of metal grow from one plate to another over time, when they get to the other side...
I bought a car that had been sold, then sat for a year* before I bought it, the battery died young which I though was likely related to being left unused.
I hadbeen waiting in a car park on a cold day, listening to the radio, and it refused to start, thankfully it was on a slope where I could let it roll forwards and drive straight to buy a new battery.
[*] the satnav showed a single journey within days of being registered, to a ferry port, and I bought it was essentially double that distance on it nearly a year later, so presumably i was driven there and back, left for a year and re-sold as 2nd hand by the same dealership
AIUI, the battery contacts are a press fit on the internal parts, being the last stage of the manufacturing process. These press-fit contacts are less than 100% reliable, and can fail at any time, leaving the vehicle with what looks like a dead battery, or one that can power small items but not the headlights or starter.
I’ve had two of these fail in that manner, both on SWMBO’s vehicles, each requiring a jump start, a careful drive home in order to avoid an engine restart, and a new battery.
I've had batteries having no problems starting a car from cold (0C) one day and the next being completely dead and not taking any meaningful charge.
The fact is that you *may* get some warning.
I was on cold mornings getting a PERFORMANCE RESTRICTED warming shortly after a sub zero start. I bought a bluetooth enabled scanner and used by smartphone to see why. There were a plethoraa of codes about low voltages, so I got the battery tested, and it was about half the performance it should have been so I replaced it and cleared the codes. (Aside: this didn't fix the problem. A huge amount of conflicting information eventually led me to inspect the coolant level. This was, when cold, just below minimum. I topped up and no codes since)
2010, if it is on it is on its original battery hardly a surprise if it has just died. Even if it was changed after, say, 5 / 6 years, not unusual.
While I’ve had batteries last longer, I work on 5 to 6 years for a car battery. Add in cold weather, short trips, lack of use, ….. and finding an old one discharged is no surprise.
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