B7 A4: Cabriolet Roof Latch Fix

[jwbeck17]

Hi, everyone. My wife had gotten home one day and said that her convertible top warning light was on. Upon further inspection, I noticed that the front of the roof rattled a bit and was a touch loose. It was able to retract, and when it did, a bolt fell out. The driver's side roof latch had gotten loose and bolts were dropping out.

Unfortunately, there at not a whole lot of detailed instructions on the A4 roofs. Even the Bentley manual treats it as an overview supplement in the back of the book. However, I was able to piece the information I collected together with the Bentley book and have put together this relatively simple DIY. It takes less than 15 minutes.

To get to the locks in the roof lid, here's what you do:

1) Open roof slightly so you have access to the front and bottom of the roof lid.

2) Remove the 9 torx bolts in the black steel strip with a T25 screwdriver.

3) Use a trim pry tool or something similar to slide between the black steel strip and the trim near the middle of the roof and pry forward. The steel strip is attached to the front weatherstripping section and had adhesive to the roof only on the ends. With some minor force it will separate. You will not have to remove it fully.

4) Grab the edge of the roof trim and pull downwards into the cabin. The trim is held in place by 4 pressure catches, so it pops right off.

5) Now you have direct access to the locks. The left and right side lock are held in place by three 5mm hex bolts. Torque them down by hand tightly.

Reinstallation is opposite of removal.

That's it! A Very simple job. Will try to add pics for reference.

Hope you find this helpful!

[jwbeck17]

1) Unscrew the 9 T25 torx bolts in the roof front black steel strip. You will see I got a few off.


2) Pry black strip from trim towards the front of the car. There is adhesive on the two ends, but none in the middle, with a little effort it will separate and pull away from the trim for you to get to it.


3) Pull the trim directly down into the cabin. It will pop off as it connects using 4 pressure catches.


Here is a shot of the inside of the trim to show you the catches.


4) Now the latches are exposed. They are attached to the roof with three 5mm hex bolts, and those are the ones that tend to get loose after a few years. Just twist then tight, then put everything back.

[WtA4WtQ5]

Nice write up. Did the flashing top light clear itself. What were the fault codes?

[jwbeck17]

Actually I didn't even check on the fault codes at that point. I just figured that the loose roof was the culprit. However, I ran the codes shortly afterwards for another issue and there were no roof codes found, so it didn't trip anything.

[jwbeck17]

Oh, and yes, the roof light did shut off. Unlike the CEL/MIL, the light basically turns on when the roof connection is bad, but turns off as soon as it is connected securely.

[S4KEN]

Does anyone happen to know the part number for the 3 bolts that go with the latch? I purchased a used s4 cabriolet and im missing one causing the soft top not secure light also... I cant find any information anywhere. I know i resurrected this post but i believe this is a common occurrence so part numbers would be a great addition.

[nate589]

Thanks for this write-up, which I used as the starting point for fixing a similar problem with my 2003 A4 Cabriolet. The symptoms were similar: the soft top would not open or close and the roof warning indicator light would flash 10 times when the car was turned on.

I followed the instructions in the owners manual to manually open and close the top and by experimenting determined that (1) when the top was down, I could start the closing process but it would stop intermittently and after multiple presses it would fail to engage the front latches to complete the closing proces; and (2) when the top was up (after manually closing it) and I engaged the top switch to try to open it, I could hear a motor whirring but nothing happened.

VCDS showed three faults:
02000 - Switch Position
008 - Implausible Signal
01996 - Convertible Top Lock Switch (F294); Open
008 - Implausible Signal
01995 - Convertible Top Lock Switch (F295); Closed
008 - Implausible Signal

Starting from the roof open position (which I set manually), I made a log of Measuring Block 1 using VCDS and compared it to this video:

https://www.youtube.com/watch?v=Q_SumTD87lQ

This along with watching Measuring Block 1 while I manually opened and closed the latches confirmed that sensors were working properly but the latches were were failing to work with the motor.

I followed the instructions in this thread to remove the trim and expose the front latch area.

With the top closed, by looking into the key slot where the manual locking and unlocking key is inserted while pressing the top switch to start the opening process, I could see that the motor was spinning some gearing but those gears were not engaging with the arms that open and close the latches:

Disengaged gears - Copy.jpg

I removed the bolts from the bracket to get better access to the back of the motor housing: After that, I could reach my hand behind the motor assembly and found that one of the bolts was totally loose (the one that my finger is touching):

Loose bolt - Copy.jpg

I then unscrewed the bolts that secure the latches to the top and removed entire motor, arm, and latch assembly. I then removed the bolts on the top of the motor and re-seated the motor assembly so that it fully engaged the gears. After that, I put everything back together and it worked.

[Nickadams]

My problem was similar to jwbeck17 as I understand his issue. My top goes up and down without a problem. The problem is when the top is fully up, the roof warning indicator light remains lit and the message "top is not secure" flashes. When the top is fully down, there is no error message. The top appears locked and secure in both positions. I did what jwbeck17 did (thanks), and found a missing bolt that should help secure the latch and all other latch bolts in varying degrees of looseness. I tightened all bolts and temporarily replaced the missing bolt. Did not solve the problem. The VCDS showed the 02000- Switch Position 008-Implausible Signal Intermittent and 01995 Convertible Top Lock Switch (F295) Closed 008 Implausible Signal before the above repair. At least so far, after the repair, there are no codes associated with this issue. I think jwbeck17 solved part of the problem but. . . Thoughts? Thanks

[06SilverA3]

I have a related problem with my '09 A4 cabrio I'm hoping someone here can help with. I just installed a replacement top and cant figure out how to reattach the weather strip seal on the leading edge of the top where it seals against the top of the windshield frame. I expect those here encountered this when accessing the front latch motor, when reassembling. I didn't pay enough attention when removing it and now can't figure this out. After extensive searching I can't find any info on this.

Any help is very much appreciated.