'09 A4 Roof Intermittently Stops Part-way

[spuk87]

Hi all, new to the forum but have been lurking trying to fix this for about a month and have not found any other post in the exact same situation.

In one month of ownership the roof has stopped moving via the switch about 4-5 times now.

Symptoms etc.:
1) Can happen from open or closed
2) Every time, it will begin to open/close and then stops when the deck lid unlatches. The deck lid does not then go up, it just hangs on top of latches about an inch up from the car.
3) The roof orange light on dash flashes throughout this, even after letting go of the switch once it has 'jammed'. NO warning messages are on (e.g. check trunk shelf).
4) Maybe unrelated, but it seems to have strong correlation with hot weather. Has only have done this on very hot days 75F/24C+.
5) The following parts were all replaced by Audi according to the service paperwork I have, in 2018 - Top pump solenoids, N22 convertible top locking motor, F201 compartment cover open position switch, F293 convertible top compartment latch switch, Convertible top motor pump.
6) I have found this guide (and the link within it) but it didn't quite seem to correlate with the problem I'm having, though I am planning to have a go at it this weekend potentially.
7) To fix, I either have to manually lock/unlock the roof and use the T-key, or a couple of times if I just lift the deck lid up all the way it then carries on working again.
8) I have manually closed, open, closed the roof to reset the system and switches and it has since failed twice after that.

I have found this guide to renew the motor (point 6 above) but given that it was replaced recently (if the motor is part of the "convertible top motor pump", or is it just the pump excluding motor?) and seems to be deck-lid related more than motor itself it makes me think it's a sensor or switch related to deck.

Anyone got any ideas?

 

[petetheprop]

I had similar issues on my old a4 cab, removing the motor and cleaning the brushes is a good start.
Ideally you need to read the error codes with vcds vagcom software, that should point you to the sensor that is failing.
For me it was the hood position sensor g356 which is a rotary switch on one of the rear hood frame hoops. For me I just took the switch off sprayed in some contact cleaner and worked it a few times and refitted it and it worked without issue from then on. There are a few guides and YouTube videos of how to get it off, only need to part open the roof and one screw so it's a fairly simple thing to check but failing that get the codes read and see from there.

 

[spuk87]

Thanks for your reply!

I bought an OBDEleven (alternative to VCDS) and ran that, showed a passive fault code 02000 as seen here on Ross-tech website: http://wiki.ross-tech.com/wiki/index.php/02000

Unfortunately that's the only code, so it doesn't pinpoint a specific sensor or switch. I tried taking out the G356 and cleaning it though it looked pristine, to no avail. I'm beginning to think it's deck-lid latch switch related, as the fault always happens immediately after the deck releases its latch. Perhaps if the latch switch is not functioning, it would explain an implausible signal because other sensors are telling the system that the deck is unlatched.

I'm not familiar with VCDS or OBDEleven yet, so I don't understand what it means to check the Measuring Blocks etc, but maybe that will give a clue?

 

[Bognorgaz]

I found that the hydraulic fluid was low, I’ve had no issues after filling it to the correct level

 

[spuk87]

Hmm interesting. Maybe it is worth getting to the pump and checking the fluid and cleaning the commutator.

I heard in a YouTube video that the hydraulic fluid is just brake fluid, if so, do you know what type? Or did you buy the specific stuff from Audi?

 

[Bognorgaz]

Comma MVCHF hydraulic fluid from Halfords is what you need. 12.99 for a litre.