A2 1.4 petrol - Faulty CCCU suspected

K

Kashou

Member
Hello A2 owners,
Nice to (virtually) meet you all!

My mom bought an Audi A2 in 2020 and I have driven it the majority of time since. Despite being old, it's a very pleasant car, and I hope to help her keep it as long as possible.
In early 2021, electronic problems showed up and they only added up. I highly suspect the CCCU. Here is a list of the problems in appearance order (if it's usefull) :
  1. The sound alarm when you leaving the car with the headlights on is not working anymore.
  2. Electrical windows both from driver and passenger side are not working anymore (maybe the most annoying problem)
  3. The fuel trap door can not be open with the button near the drive's seat (I have to open it manually through the boot)
  4. Driver's door is not responding anymore to the central locking (note that we don't have remote key).
  5. The locking/unlocking button on the driver door is not working anymore.
  6. Sometimes, the boot lock does not repond to the central locking system (quite annoying too).
I think it's all. Besides that, everything else works fine (but I think there is only the air conditioning left...).

Last summer, we naively bought another CCCU thinking that simply changing it would solve everything, but as you probably guess, it does not. I only learnt lately that it has to be pre-programmed for the specific car. Note that I don't have a VCDS from rosstech and it seems quite expensive so if I could avoid that...

I am new to the forum and I have spend the past few days searching for solutions. I will soon contact timmus which seems to be the expert in this field and I am highly interested in his CCCU replacement service. I'm also interested in others opinions maybe my case might help someone else in the future :).
I also suspect the battery (I think it's still the original), do you think a faulty battery could be the cause to all the problems ?

Thank you very much!
Yours faithfully,
A fellow A2 belgian owner
 
Timmus is definitely the right man to go to!
For a start, what is the part number on your CCCU? Early ones are known to be unreliable. Some of you symptoms could be door microswitch related.
 
First question I have is how old is the car battery and is it the correct one for the car. Many electrical issues are down to the car battery so is a sensible place to start.

You are wrong about VCDS being expensive. Provided you have any laptop that has a USB port and preferably Windows you download the free version of VCDS Lite directly from Ross Tech and buy a KKL cable from ebay and you are good to go. The Lite version can be made better by registreing it and paying the fee.
 
Classic symptom of broken wires at the hinge grommet. You can pull back the rubber 'bellows' from the body to the door to reveal broken wires. I've seen this many times now, not only on A2's but also on an A3 we repaired recently. If they are broken, its a simple case of removing the loom from the door and soldering the broken wires, or there are repair kits available on ebay for this purpose.

Ian
 
Thank you all for your responses !
simufly said:
Timmus is definitely the right man to go to!
For a start, what is the part number on your CCCU? Early ones are known to be unreliable. Some of you symptoms could be door microswitch related.
Click to expand...
The original CCCU is numbered : 8Z0 959 433 S
The one that i bought as replacement (but didn't change anything as I can't/don't know how to program it) is numbered : 8Z0 959 433 N
audifan said:
First question I have is how old is the car battery and is it the correct one for the car. Many electrical issues are down to the car battery so is a sensible place to start.

You are wrong about VCDS being expensive. Provided you have any laptop that has a USB port and preferably Windows you download the free version of VCDS Lite directly from Ross Tech and buy a KKL cable from ebay and you are good to go. The Lite version can be made better by registreing it and paying the fee.
Click to expand...
To be honest I'm not sure how old it is but if anyone can tell with those photos I would be thankful !
battery1.jpg

battery2.jpg

There is also a tiny white sticker on the side with the number 358046055.
I bought a KKL cable on ebay but the delivery might take a while. Thank you for your advices!
Kleynie said:
Classic symptom of broken wires at the hinge grommet. You can pull back the rubber 'bellows' from the body to the door to reveal broken wires. I've seen this many times now, not only on A2's but also on an A3 we repaired recently. If they are broken, its a simple case of removing the loom from the door and soldering the broken wires, or there are repair kits available on ebay for this purpose.

Ian
Click to expand...
I have to change the door check (8z0 837 249) on the driver side so I will check the wires once I get the pieces. Thank you!

Kashou
 
As it is an 8Z0 ( from its part number ) battery safe to say it is the original battery the car left the production line with. Now well past its best and a replacement certainly justified.
 
Good Evening,

I think possibly the battery dates from week 10 of production year 2002 but it is difficult to read clearly. This kind of code can usually be found inscribed on the top of the negative post, clean it up and post a closeup.

Andy
 
As the original battery deserved the final rest, I replaced it with another one which is a few years old but was never used (I ordered one and receive two for another car). I obviously charged it before making the change and surprisingly things got... worse ?
I can no longer unlock/lock doors and the boot through the passenger door as I used to until now. Well, more specificaly, it works one in maybe an hundred times. It's very weird... So i'm guessing there is only the CCCU left as the gulty.

I should probably connect the original battery the see if it works again or if the loose of central locking is simultaneous event but unrelated to the battery ?
I already tested to lock while the engine is running and also with another car (audi Q2) connected to the battery with jumper cables but it didn't change anything.

As Kleynie suggested I checked the wires at grommet wires and didn't see any broken/damage cables. I guess I can check the continuity but I'm not sure how to do it.

I'm sorry if my descriptions are confusing/unclear, I try to consider all possibilities while writing.

So for now I will wait for the KKL cable to arrive and in the mean time I will contact Timmus regarding the cccu.
Thank you all again for your help !
 
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