Battery drain single wire error help!

[dr_schnell]

Hi all

I hope someone can help as I am at the end of my tether with a battery drain problem.

I have a problem which was draining the battery almost overnight, I think the car has previously had some issues regarding drains according to some of the service notes so I took it back to the dealer that supplied the car (non-VW), they didn't instill allot of confidence and idn't fix it after 2 tries  so I decided to try and resolve the issue myself.

First thing I did was to buy a new battery, no solution.

I then pulled the fuses to identify which circuit might be at fault, this was successful and identified the fuse linked to the rear power windows and the central connivence module. With this fuse removed no battery drain but I think my alarm is not set and I'd like a permanent fix.

Since that I have managed to get a vcds scan and the only error is a
1 Fault Found:
00470 - Combination comfort Databus in Single Wire
011 - Open Circuit


After a bit of reading on the net  I assumed that it was a cracked wire in the door hinge but of no avail. all look fine in drivers and passenger doors.

I have narrowed it down to the rear drivers side door as you can hear that it locks slightly out of sync and a measuring block test identified that it is working in 1 wire mode.

Therefore I replaced the door module... but with no success.

Any thoughts would be greatly appreciated, I should mention that an after-market tow bar has been added and roughly spliced into the rear lights, could this be a potential source of problem?

[Eddie-NL]

where are you located?

[dr_schnell]

Hi Eddie

Sadly in NI, otherwise I'd have requested your help.

Just a further note to say that it has an updated can gateway supplied by yourself  so that isn't at fault.

I also changed the central connivence module over and gain no fix. 

[Ruthlessness]

where are you located?

Hi Eddie,
Is there any chance i get  a contact number for you,
I too have battery drain and could really do with some help.

[Eddie-NL]

07954653918

[dr_schnell]

Folks

Bumping this up from the past.

I really need help finding a solution  , I left the fuse which I identified as being related to the drain for the last while, we have young kids so no rear windows was of no concern, however I have sold the car and I want to rectify the problem for the new owner.

Accordingly I have given the car to a local auto electrician, he diagnosed that the control module for the aftermarket towbar was faulty and duly replaced it, however this is not solved the problem as the battery is still draining.

He was convinced that there was no pull at the door in question.

So any ideas would be greatly greatly appreciated as I don't want to lose the sale as I am due to collect the new car this week 

To recap, there is a battery drain which is linked to the rear electric windows, disconnection of the door wiring for the driver side door stops the drain. A block module test confirms that this is operating in a single wire.

If you are sitting in the car it does sound like one of the relays is constantly clicking every 5 minutes so I'd be fairly certain that the central connivence module is not shutting down.

I have replaced the following

Battery
Rear wiring loom (admittedly a 2nd hand part)
Door lock module
Central connivence module (admittedly a 2nd hand part)
New can gateway for RCD510 upgrade

None of these have solved the 00470 error or the battery drain.

Any thoughts??