£900 folly Repair 1. CCU replacement

[Oskar]

Hi.
Based on my initial intro post, where I have outlined the work I have in front of me to get my A2 up to scratch, these posts describe each repair or upgrade.

1. CCU replacement due to Central locking cycling.

I had hoped that the CCU was the cause of not only the cycling, but also the fuel flap and drivers electric window, but things are never that simple!
I have an older A2, so the CCU needs to be an early suffix to ensure the key remotes still operate at the right frequency. Mine was a Q suffix so I found on ebay an 8Z0959433Q CCU from a 1.4 TDI. It had broken plastic around the clip area, so was cheap at £54.95 incl freight. It was a gamble.

Thanks (and all copyright to) MtlCarGarage

it appeared to be a simple process to replace this (and it was), although I was not sure if I needed to disconnect the battery first. As this was not mentioned (and his videos are so thorough, it would have been), I assumed not and went ahead without disconnecting.

The unit worked immediately, and all I had to do was use VCDS lite to check the coding and other aspects as described by MtlCarGarage again, here in part 2

It was important to check the additional items, as my replacement CCU was not coded for Air Con, which may have been tricky when it gets hot.....

I got the key coded straight away, and everything else appears to be fine, so a good success. No cycling, but no fix for the other issues I have (fuel flap etc), which upon furthe VCDS investigation, were not CCU caused anyway (assume micro switch in drivers lock - refer to post Repair 2. when I put it up).

The broken connector area was not an issue, nor do I believe it will become one. The TDI source also does not appear to be important, as the interior kit is all the same.

Let's see how long it lasts........

Cheers

Matt

 

[birtyA2]

Yes these videos by @mtl are truly a joy to behold and really helped me when I first got my A2 just over a year ago as does having @Ami right on my door step

J

 

[Proghound]

Welcome aboard, and good to see a plain-english write-up of one of the common pitfalls of an earlier A2. The older generation CCCU's have a dodgy chip which fails with various symptoms, cycling of the locks every so-many seconds is one of them. You've clearly done your homework to know to get another one of the same frequency, but by replacing it with another one from the same generation, unfortunately you've only delayed the onset of further problems. A better solution which you could still employ, would be an AF-suffix CCCU and a pair of the D-suffix fobs which transmit on its frequency. You just need to split the fobs and attach their button-halves to the keyblade-halves of your non-suffix fobs. New batteries (CR2032) while they're apart, pair them to the CCCU and job done.

 

[Oskar]

Thanks for your reply Proghound, and your info. I may do a replacement key post, as I have had trouble here. I knew I needed the same frequency, so when I bought an Audi key of 433.92 MHz that looked the same, I thought all was well. I could never get it to work, and it appears the 'D' element is the key. Same frequency, but not quite the same. I did manage to get a 433.92 TEMIC key, which worked fine. I will keep the D key if I need to replace the CCU again in the short term (which I sort of expect to).

Are there any more coding options available in the new suffix units, or are they basically the same?

Cheers

Matt

 

[Proghound]

The one to get is the AF, unless you have all four electric windows, when you can get away with an AE. The AF has extra circuitry to talk to the rear door locks direct when the car has manual rear windows, rather than via the rear controllers for electric windows. So the AF can be coded for either situation.

 

[Oskar]

Thanks. Locks are another story, but I will see how I get on with fixing my Drivers Front next weekend. I plan to change the micro switch first, however it may well be a solder issue. I am just hoping..........