pompeyal

Sorry I couldn't help...

Hi Radish, yes after a wild goose chase I finally found out the cause to my problem, there was a short circuit on the glovebox locking motor which was blowing the fuse to the comfort unit under the carpet in the passenger footwell, one of the plugs that is on the unit has only 2 wires which supplies the motor, I have removed the plug from the comfort unit and now the fuse stays as it should, both of the wires of this particular plug are both shorting to earth. I have used my Foxwell Pro scanner to finally sort out the problem, several times when checking the errors most of the faults were leading to security problems such as errors on door locks, petrol filler cover locks which were thrown up when locking the car using the fob, each time the comfort unit fuse blew. since removing the plug all as been well. The roof electrics is controlled through the comfort unit and when the fuse blows you get the roof error message (roof unavailable) try replacing the blown fuse and try the roof, I did and it worked as normal until I locked the car and the fuse then blew. I hope this helps you sort out your problem because I know how much frustration you must be going through trying to find this fault, it took me ages to finally find exactly what my problem was. The glove box lock motor is only activated when locking the car as it locks the glove box then. The boot problem also went away after removing this plug, I am sure this problem was caused because they share the same circuitry.

Could also be a wheel bearing, buckled wheel, under inflated tyre to add

Does anyone know which of the 3 large relays withing the J393 unit controls the cabrio roof? Cheers Alan.

Hi all, Does anyone know if the above unit the same throughout the range, i.e. saloon, avant and convertible? Also does the numbers 8H0 959 433 K on the unit have to exactly match. Thanks.

Hi Gareth, thanks for the reply I will get onto the checks as soon as I get hold of a suitable meter from work, as far as the cable breaks go, I have stripped back all the bindings on the boot harness as far back as the boot bulkhead going into the cabin and no damage there, that was my first port of call, thanks for the mention though. Regards Alan

Hi all, bet none of you can help but here goes, I have a 2006 A4 Cabrio which has the following problems, they all happened at once so....1, the boot will only operate using the key, the switch and the fob do not work, I have checked all the wiring from boot to the comfort unit under the passenger seat and all OK, no breaks or shorts, the actuator is functioning as well as all the boot operation micro switches. Have looked inside the comfort unit but nothing obvious and circuitry checks out. 2, The roof does not operate under power, only manually, dash says not available when trying to operate by the switch, I have manually opened and shut the roof several times as some suggest as a fix to no avail. 3, The battery keeps draining. What I have noted is that the power cable to the boot actuator reads short circuit but I do not know if that is the default when not in operation, I have checked the cable run for breaks back to the comfort unit and checked continuity end to end and for shorts with the cable disconnected at each end and this proves OK. I am thinking maybe a relay has broken down the other side of the comfort unit causing the short which is draining the battery, all fuses in the main fuse box are OK. Any suggestions please..

Sorry but you know what they say, every day is a school day...lol

I know how you feel, a URL is the writing in the address bas such as www.audiownersclub.etc/etc Ooooo sorry I told you lol

Hi Gareth Have you got the URL for that find, I haven't had too much success. Regards Alan

Hi Magnet, I have followed each of the wires from their plugs ( Barrel, Actuator, Latch and Lift button ) right back until they go into the main bound loom at the rear N/S wheel arch, I would like to know where the red/yellow wire terminates as this is the one that is showing a short. All of the micro switches are correctly functioning and the actuator works correctly. I have removed all of the connectors from the switches and actuator and checked with a meter all of the cables to earth, all of the brown cables read short to earth which is correct along with the red/yellow which shows short to earth which is not correct, the remaining cables are open circuit which is correct.

Hi, would anyone be able to post up a wiring diagram for the boot latch please, cheers Alan

Thanks for getting back Magnet, as you have read in my posts, I am pretty sure the red/yellow cable from the boot latch actuator should not read short circuit but when switched it would show voltage, as this cable shows a short circuit to earth would this not be the problem area? I will go through the procedure with the meter across the earth terminal and lead and pull fuses to try and find the circuit, I can't find any info on the boot release fusing anywhere on the master fuse box, I have pulled the front door fuse whilst monitoring the short on the red/yellow cable at the actuator and it still shows short with the fuse removed, I removed the comfort control unit fuses and it still showed a short, does the boot share another fuse with something else do you know?

Right after spending more hours on this problem to no avail has anyone got a wiring diagram for the boot latch activator showing the red/yellow wire route and termination please? Alan

Hi all, My car is a 2006 A4 Cabrio and I have an electrical fault and would like some assistance if possible, I have trolled the forums covering similar faults and I have done some investigations, what happened is the battery went flat for no apparent reason and when I started it again the following faults appeared:- 1, the boot would not open using the remote control (the doors work fine) 2, the roof will not actuate (Open or Close) 3, the battery drains after approx. 24hrs. (If I drive the car daily the battery holds till the next day) What I have done so far:- 1, I have checked and fully charged the battery, that is fine 2, I have checked the switches at the barrel, latch, and release mechanism, they function correctly 3, I have checked the actuator that is fine 4, I have manually opened the roof and closed it to reset and nothing different, (roof does not work and i get not available message, on switching the ignition on the roof warning icon on the dash flashes until I start the engine) 5, I have checked the loom from each switch and the actuator as far as I can back to behind the right hand boot lining for breaks, none found. 6, I have metered the earth (brown cable) at the Actuator, Barrel, Release and Latch they show good grounding. 7, I have metered the Barrel live (Blue cable) that shows no voltage 8, I have metered the Latch live (White cable) that shows no voltage 9, I have metered the release live (Grey cable) that shows 12volts 10, I have metered the Actuator live ( Red/Yellow cable) that shows short to earth. Can anyone please help me further? I believe the roof doesn't work because of the boot release has a fault and it the roof electrics can't determine if the boot is not shut it will not open. Questions:- Is there a relay that may have gone faulty, if so which one and where do I find it? Has anyone got a wiring diagram which covers the boot harness and where it is controlled from? I have seen several times people who have had the same symptoms and the majority of the time there has been broken wires or the boot release actuatorhas gone faulty, If only that was the problem with mine but its not, has any of you guys had the same problems as me, if so how did you overcome them? Cheers Alan