Comfort Control Unit clicking (sounds like a turn signal flasher)

[Shenandoah]

Folks,

This is in my 2000 Audi TT -> TDI conversion. The Comfort Control Unit (located on the driver's side under the small side window) has for the past year or so made "clicking" sounds like a turn signal is on. This doesn't happen that often, maybe once a month. It might "click" for a minute or sometimes longer before it stops. I'm not sure if does this at other times (middle of the night, etc.).

Yesterday I went to start the car, but the battery was very low and wouldn't start the car. I had just driven the car the day before. Battery is a year old. I put the charger on the battery and charged it back up. I came out to the car noticed that the CCU was clicking away, like the turn signal was on. I opened the doors, opened the hatch, and it continued on. I tapped the interior panel a couple times where it's located. Eventually it stopped clicking. I did a "google" search and found that other folks had similar problems and replaced the CCU. There is an alarm relay in the CCU that fails and will run the battery down? I noticed YESTERDAY that when I lock the car, the alarm horn does not "beep" whereas in the past it did. I ran a scan with VCDS but no codes showed up.

I can pick up a used CCU for around $100, but wanted to see if anyone else has had a similar problem with their VW? And if they did have a similar problem, was it the CCU or something else that affected the CCU.

Thanks!

Eric

 

[Powder Hound]

Since there are a number of relays in the CCM, it could be that one or more of them are failing. Just replacing with a known good unit would be preferable to the nearly impossible task of finding replacement relays and then doing the R&R on the CCM you have.

Do you have a part number? If it is the same rather common one that was used on the same year(s) of Golf, Jetta, and Passat (probably NBs as well) then I have a spare I can ship for $50.

Cheers,

PH

 

[Shenandoah]

Powderhound,

Thanks for the reply. I was thinking the exact same thing: Just replace the unit with another one. I have four "parts" cars, two Golfs, a Jetta sedan and a New Beetle, so I have some options. I'll have to pull one from the Golf and the New Beetle to see if they are the same size and number of wiring connections as the one in my Audi TT -> TDI. The Audi module is part number 8n8 962 267 a, so I know it's not a the same as a VW module (at least the part number isn't the same).

If I have time, I'll take a look at the wiring diagram for the Golf module and compare it against the Audi module.

I did disconnect the connector to the module that supplies power and haven't had any problems with the battery draining/running low.

Eric

 

[BobnOH]

WAG- Somewhat common problem on many cars is the factory lube inside relays gets corrupted with metal flakes causing unwanted contacts. Simply clean it up.

 

[Powder Hound]

Those relays inside that module are very small. Just opening one of them up would be a chore, and possibly not doable. But there are people out there with amazing skills, so it can probably be done. Not by me, but it probably can be done.

After some work, I found the solution to my problem was replacing fuse #14. Just wish I knew where my fuses are (just moved...) instead of having to buy a new one.

Cheers,

PH

 

[Shenandoah]

I pulled the module out of my Audi TT yesterday and opened it up: there were six or more relays that are soldered on the circuit board. No way to "open" them up without destroying them.

Eric