Question on keys...

I just replaced the battery in the spare key that came with the car (it works physically but not for remote locking).
At the same time I thought I'd replace the battery in the main key, just to be safe.
Now, of course, neither key works remotely :(
Is there a way I can get them working again? Maybe there's some re-authorising I need to do?

Thanks!
 

2work

A2OC Donor
There are quite a few threads about this after you change the battery. From memory though, I think you just need to manually unlock the car, put key in ignition, turn ignition on then press the lock or unlock button on the remote fob for a few seconds.

What I described above might not be quite right but worth a try as it won’t damage anything. Failing that have a search through the forums or how tos.

Kind regards,

Tom
 

Clackers

Member
I have the same problem with a car I bought a few weeks ago, but having tried this method out, it still doesn't recognise either key, they are both fine for opening via the lock though...
Is there a way of coupling the keys if they were not originally the key for the CCCU? I think it may have had the CCCU changed possibly, hence neither key works...
 

Edwrai

Member
I have the same problem with a car I bought a few weeks ago, but having tried this method out, it still doesn't recognise either key, they are both fine for opening via the lock though...
Is there a way of coupling the keys if they were not originally the key for the CCCU? I think it may have had the CCCU changed possibly, hence neither key works...
You need to check the part number of the keys to the part number of the CCCU as not all a2 fobs will pair, also my mind is hazy on this as I haven’t done it for a while but I think there is a VCDS process too.


Sent from my iPhone using Tapatalk
 

2work

A2OC Donor
If you need to programme keys due to CCCU swap over, this (thread #6) is the process I’ve successfully used a few times. Of course you’ll need to ensure you have the correct fob for the CCCU first.

Kind regards,

Tom
 
OK, I've tried the process outlined in @mrbroons video and here are the results:

Key that worked remotely before battery change: Works* again!
Key that hasn't worked remotely before change: Still doesn't work.

So, I have remote central locking again.
However, note the *... What doesn't happen, and as far as I know in my short time with it so far, is that the front electric windows/OSS don't automatically close upon locking.
Is this something that is configurable?

As far as the second key goes, it works physically and that's enough for use as an emergency spare.

You've mentioned a bunch of 4-letter acronyms, I'm sure I'll find some material to read up on the electrical/electronic architecture and understand them better.
 

Proghound

Admin Team
What doesn't happen, and as far as I know in my short time with it so far, is that the front electric windows/OSS don't automatically close upon locking.
Is this something that is configurable?
Yes, the windows up/down on lock/unlock is configurable in VCDS although I believe that was included in the default settings (at least for the UK). You have to hold the button on the fob down for a second or two to make them do this. This didn't extend to the OSS though, that always needs to be opened and closed via its button on the interior lighting panel.
 

Andrew

A2OC Donor
OK, I've tried the process outlined in @mrbroons video and here are the results:

Key that worked remotely before battery change: Works* again!
Key that hasn't worked remotely before change: Still doesn't work.

So, I have remote central locking again.
However, note the *... What doesn't happen, and as far as I know in my short time with it so far, is that the front electric windows/OSS don't automatically close upon locking.
Is this something that is configurable?

As far as the second key goes, it works physically and that's enough for use as an emergency spare.

You've mentioned a bunch of 4-letter acronyms, I'm sure I'll find some material to read up on the electrical/electronic architecture and understand them better.
One thing at a time.

The second key that does not work remotely. I can see five scenarios.

1. The key has never worked. Possibly a replacement key that has never been paired to the CCCU with VCDS. This needs doing.
2. The key is a replacement with the wrong part number/frequency. It will never work.
3. The key is genuinely faulty. Buy a new key.
4. The new battery is duff. Try another battery.
5. Something I have not thought of! (A mathematician always includes the complement so they are always right!)

Start by checking 2. Split the keys = seperate the two halves as you did when inserting new batteries and compare part numbers, you might need a magnifying glass!

Andy

Edit. The D or not after the part number is important.
 
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Jeff Sutcliffe

A2OC Donor
You've mentioned a bunch of 4-letter acronyms, I'm sure I'll find some material to read up on the electrical/electronic architecture and understand them better.

VCDS = VAG COM Diagnostic System. It's a thing that experts use by plugging a cable into a socket somewhere above the brake pedal and the other end into a laptop with the appropriate programme, which is a paid for download from Ross Tech. It has loads of features that I don't understand but can read faults and, in some instances, fix them.
CCCU = Central Convenience Control Unit. A box of electronic gubbins (technical term) that does things. It lives in the box underneath the front passenger footwell that you'll discover when you lift the carpet. There are lots of other electrical gizmos living down there too.
 

Howey

Member
Check part number of inop remote is a match to working one

I used diagnostic kit to code my second hand remotes (all same part number)
 

bretti_kivi

Member
OSS can be closed by putting the key in the lock and holding in the "lock" position - the windows and OSS will close for as long as you hold the key in this position.
Windows will not comfort close after a longer battery disconnect without resetting them; press them all the way down and hold there for 2 seconds, then all the way up and hold for another two seconds. Now repeat the down and hold. One-touch up and down should now work and they should respond to the key.

- Bret
 

PlasticMac

Member
You've mentioned a bunch of 4-letter acronyms, I'm sure I'll find some material to read up on the electrical/electronic architecture and understand them better.

VCDS = VAG COM Diagnostic System. It's a thing that experts use by plugging a cable into a socket somewhere above the brake pedal and the other end into a laptop with the appropriate programme, which is a paid for download from Ross Tech. It has loads of features that I don't understand but can read faults and, in some instances, fix them.
CCCU = Central Convenience Control Unit. A box of electronic gubbins (technical term) that does things. It lives in the box underneath the front passenger footwell that you'll discover when you lift the carpet. There are lots of other electrical gizmos living down there too.
The VCDS-Lite download is free (from Rosstech). Will enable you to scan and other useful stuff. Upgrade it by registering if you need more functionality ($99 - £75). Lead from eBay, about £5. Free version only works on cars up to 2005/2006, so fine for A2s (and Mk1 TTs).
Mac.
 
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Clackers

Member
Check part number of inop remote is a match to working one

I used diagnostic kit to code my second hand remotes (all same part number)
Can you check if the keys are the original paired ones to the CCCU? What diagnostic kit did you use to re code the keys to the CCCU??
Thanks
Andy
 

BobbySox

Member
OSS can be closed by putting the key in the lock and holding in the "lock" position - the windows and OSS will close for as long as you hold the key in this position.
Windows will not comfort close after a longer battery disconnect without resetting them; press them all the way down and hold there for 2 seconds, then all the way up and hold for another two seconds. Now repeat the down and hold. One-touch up and down should now work and they should respond to the key.

- Bret
I often lock my car with OSS left open.., now I have a neat trick to close it!, Thanks! :D
 

Howey

Member
Split the fob and the part number is printed on the fob part

I used a Hella megamacs, dead easy for coding a few ebay fobs!
 
OSS can be closed by putting the key in the lock and holding in the "lock" position - the windows and OSS will close for as long as you hold the key in this position.
Windows will not comfort close after a longer battery disconnect without resetting them; press them all the way down and hold there for 2 seconds, then all the way up and hold for another two seconds. Now repeat the down and hold. One-touch up and down should now work and they should respond to the key.

- Bret
Yup that worked, much obliged
 
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