Car won't unlock using unlock button on key / key won't start car!!

evapor8

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Morning all.

Just come back from 5 days away. Car was parked at airport.

I flew back late yesterday afternoon, walked to car, opened it as normal, and drove home. No problems at all.

This morning, I go to car, and it's not opening using the buttons on the key. The key itself obviously opens the door manually just fine, but the car won't start with the key in the ignition.

I have changed the battery on the key, but that made no difference.

Help!!!!

Chris
 
could it be possible your alternator has packed up and the drive home yesterday drained the car battery?
 
its the only thing that i can think of off the top of my head that will kill a car like that, does the engine even turn over?
 
Did the key in drivers door trigger the central locking, can you undo the boot from the remote, do you get the coil symbol in the cluster all the time even when trying to start.

Try disconnecting the battery of the car for 10 minutes then back on & try starting the car which will hopefully resync the remote.

Do you have a 2nd key to try with?
 
Nope. Nothing at all.

had something like this once with my old 306, one of the battery connectors had come undone... not on the actual battery, but a bit further down so could be worth checking the connectors round that and see if anything is loose, apart from that im out of ideas
 
Ah so you get no interior lights, nothing at all with power, check under the battery box if its in the engine compartment to see if the ground terminal has corroded on the chassis, I'd take it of anyway & rub it down.
 
heh I would be pretty ****** if an 18 month old car has corroded battery terminal leads. maybe loose, but if the battery has gone as well pretty ****** as well that it not last 18 months

Can you just not get another battery and try jumping it, as it does sound like the battery is dead or a main fuse gone?
 
Did the key in drivers door trigger the central locking, can you undo the boot from the remote, do you get the coil symbol in the cluster all the time even when trying to start.

Try disconnecting the battery of the car for 10 minutes then back on & try starting the car which will hopefully resync the remote.

Do you have a 2nd key to try with?

Key in door didn't trigger anything. Can't undo boot from remote. No lights at all on cluster.

I have a spare key but i don't think it's ever worked! (should really have sorted that out sooner ...)

Will try disconnecting battery and see if that makes any difference. Thanks.

does your ignition lights come on ?

Nope.

Ah so you get no interior lights, nothing at all with power, check under the battery box if its in the engine compartment to see if the ground terminal has corroded on the chassis, I'd take it of anyway & rub it down.

I'll see if I can take a look ...
 
i wonder is the battery flat as ? have you a tester ?
 
dont most batteries now have a little window that glows if the battery has charge? dont know if the audi ones do as never had to look at mine, that will tell you if the battery has charge or not, could help point you in a direction of where to look next
 
if its flat you need to find out what done it. good luck mate..
 
Nah not all have the Magiceye tbh which is crappy cause would help us alot huh.

Even with flat battery it would have to be completely dead to not light anything at all in the car, as even the lowest of voltages does power minor systems & I mean minor :)
 
Im going for flat battery too - when you used the boot for your luggage, the light inside the boot stayed on without you noticing and has flattened the battery over night?
 
I had this once a couple of years back. Battery was completely dead overnight. Even the memory in the HU went. Jumped it next day and its been fine ever since. Battery is now 6 years old. Possibly a short across the plates in the battery and bunging a starting current across them cleared it again. Jump it and see if your lights get brighter when you rev it while the battery is still right down. As Nige says, check your earth connection to the chassis. The 3.2 has a main battery fuse in the boot with the battery ?
 
i had this in my vw golf which was 16 months 0ld and the battery connection was loose just tightened it up and allwas ok
 
OK - update. It was indeed a flat battery.

Next problem was working out why. Audi went over it with whatever electronic trickery they use. They suspected that it was the 2nd rate media adaptor (like this one - KUFATEC GmbH & Co. KG - iPod Video Interface + IMA Multimedia Adapter ohne OEM Steuerunghttp://www.vwcruise.com/38.html) as it was the only aftermarket item fitted to the car.

Transpires that it's the Audi bluetooth unit drawing 3 amps from the battery even when the key isn't in the ignition!

Now this bluetooth unit wasn't a factory install ...

I've already incurred £170 of labour costs for them checking this out, and if the problem results from a 2nd rate install I shall be very disappointed!

Chris
 
there is a mention here about certain modules having problems drawing too much current.

Upgrading of Volkswagen Park Distance Control (PDC) to Optical Parking System (OPS) | my-gti.com

Thanks mate. I think the easiest (and cheapest) thing for me to do is have them whip out the bluetooth unit and close everything up again.

I can then send it back to the supplier/fitter, get a new one and flog it on ebay! And then resolve to never bother having anyone other than Audi mess with my car again! At least if they break something I have some comeback!

Chris
 
Had exactly the same thing with a kufatec multimedia adapter fitted , was resolved by having it rewired so the power was being taken from the RNSE unit so when the RNSE unit shut down after 10-15 min it automaticaly powered down the Kufatec unit.
 
£215 bill for labour. Faulty bluetooth unit and multimedia adaptor now removed.

Still no response from the vendor of these two items. No particular surprise there.

Chris
 
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guys i havent fully read this thread but i had the same issue (as in title) and can confirm its a new battery job... :superman:
 
A 3 amp drain.

The A3 2.0T uses a group 47 battery.

A group 47 battery should be in the 80-amp-hour range.

That means that a battery in god condition should be able to power a 3-amp load for MORE than 24 hours before being completely flat.

Also, 3 amps at 12 Volts equals 36 Watts of heat dissipation. That would have to be:

(1) SERIOUSLY faulty. (no BT unit should draw 3amps. Even when turned on. -It uses milliwatts of power, unless VERY faulty, and the insulation on the wiring in the harness should pretty much MELT if you pulled three amperes down it)

(2) VERY hot under the carpet, specially in its little insulated, foam-lined container... Remember, a soldering iron at 25 Watts gets pretty hot, and with the heat having nowhere to go, I would expect some significant visible evidence of heat.

So not everything in their explanation appears to add up as a credible and complete explanation.

I reckon that the battery is quite likely low-capacity (and should be tested!) unless you're holding a pretty visually obviously overheated bluetooth adaptor in your hand right now.

Keith
 
Hi Keith.

Well car was idle for 5 days while at the airport. Probably the first time since the bluetooth was installed that it's remained undriven for that long.

Battery has been tested (so they tell me!)

I thought (but am not certain) that Hazzydayz install the bluetooth unit in the dash somewhere??

Wiring harness is allegedly ok and has been left in situ in case I decide to refit a replacement unit. No singe marks or dubious smell on the removed "faulty" bluetooth unit. Install was said to be done properly.

Chris
 
I never put the module behind the dash, never, always under the seat, the wiring can handle that current imho aswell, but 3amps does seem a shed load for that module, I'm gonna test mine now & also see if this is an issue for me as my battery is also getting murdered by something when its idle, even if its a newer module.
 
I never put the module behind the dash, never, always under the seat, the wiring can handle that current imho aswell, but 3amps does seem a shed load for that module, I'm gonna test mine now & also see if this is an issue for me as my battery is also getting murdered by something when its idle, even if its a newer module.

To be honest Nigel, it may have been under the seat, but I always had it in my head that it was behind the dash somewhere. Didn't see where it was placed when they fitted it.
 
Just after having a similar problem myself, unlocked the car about an hour ago with central locking, 15 minutes later I got out and the key wasn't working

locked via keyhole, got back in a few mins later with key in door, the central locking isn't working nor are the windows,
car starts up fine and all other electrics work fine like audio and heating, seems just the central locking and windows are affected anyone know what it could be?

Thanks


Also the battery went very flat last week after I had the lights and music on while washing the car, had to get a jump which took a while so not sure if that has something to do with it
 
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My TDI sport switches the radio off automatically after a certain time to preserve battery power ( I assume ! )

Maybe you need to re-synchronise the key with the car again ?
 
Old bluetooth unit sent back, and new one arrived this morning.

New HW is 8T0862335E H42, SW 8T0862335E 0650

I assume this is a much newer one?

Chris
 
This could be the path I take now tbh, just filtering out whats causing the drain.
 
Just after having a similar problem myself, unlocked the car about an hour ago with central locking, 15 minutes later I got out and the key wasn't working

locked via keyhole, got back in a few mins later with key in door, the central locking isn't working nor are the windows,
car starts up fine and all other electrics work fine like audio and heating, seems just the central locking and windows are affected anyone know what it could be?

Thanks


Also the battery went very flat last week after I had the lights and music on while washing the car, had to get a jump which took a while so not sure if that has something to do with it
i had this problem after my car was parked up for two weeks while i was on holiday i opened the boot and it must have reset itself or something because now its fine weird