A8 Parts Forum - Help with boot lock problems ...

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- - Help with boot lock problems ... (https://forum.a8parts.co.uk/showthread.php?t=14073)

Help with boot lock problems ...

I'd be grateful if someone could explain how the A8's boot lock works so I can try and diagnose a fault.

As of yesterday, when I shut the boot I no longer hear the 'clunk' as the lock operates so I guess something's wrong.

I have the motored version; if I push the button, the boot closes and then reopens.

If I manually close the boot, it stays shut [thankfully] but I get the warning on the DIS that the boot is open.

Thanks - Julian

Mine had the pull-down (soft close) motor fail on it and did that - did it have that on yours? could be the soft close motor itself or the cable running to it (this is different to the actual boot open/close motor) :Confused:

Sorry, I don't understand what you mean by the soft close motor.

The boot motor and cable that open and shut the boot are fine; my problem is that when the lock mechanism in the boot door comes down to meet the locking plate, there's no longer a motorised 'clunk' as the lock 'wraps around' the locking plate pin.

I'm hoping that someone can tell me what triggers the motor activation and what could have failed on my car.

Thanks & Regards - Julian

I think there's a micro switch in the latch part of the lock (your first picture). I had the same problem and sprayed copious amounts of WD40 in and it's worked ever since

Quote:

Originally Posted by 47p2 (Post 140540)

I think there's a micro switch in the latch part of the lock (your first picture). I had the same problem and sprayed copious amounts of WD40 in and it's worked ever since

Thanks for that suggestion; will have a look in the morning.+++

Julian

Quote:

Originally Posted by JulianHicks (Post 140531)

Its called "Power Latching System" by Audi and has a bowden cable going to a small motor - see pictures attached.

Julian,
There are two motors involved.
The one that Neil has pointed out is on all cars and is the one that locks the boot.
The other motor is the optional one that powers the boot lid up and down. This is for idle folk like me. :D

So I've only just read the updates to this thread as I forgot I was going away for the weekend :o

It's my locking mechanism that's not working; I've just had a look and I still can't work out what's going on when the 'black box' on the boot lid comes down and fits into the slot with the pin in it :-(

[Although I do now realise there's some sort of cable that gets pulled somehow from a motor in the boot thanks to the diagrams above].

But I presume:
a) the 'trigger' for the process is the boot coming down and the 'hook' in the boot lid box triggers the motor that
b) gets the motor to pull
c) the cable that's attached to the pin in slot.

So I guess the problem could be in any of these parts? Does VCDS have tests I can run to see which bit may not be working?

thanks - Julian

PS Just realised that I've had a few DTCs in my VCDS scans in the last six months but couldn't work out what part that was.:(

Code:

Address 46: Central Conv.        Labels:. 4E0-910-289.lbl

   Part No SW: 4E0 910 289 A    HW: 4E0 907 289 

   Component: Komfortgeraet   H04 0040  

   Revision: 00400004    Serial number:  W040411110043

   Coding: 0000249

   Shop #: WSC 02313 785 00200

   VCID: 275D9CFD963CD57EF0-8072



   Subsystem 1 - Part No: 4E0 910 853 

   Component: Heckdeckel   P14H06 0070



   Subsystem 2 - Part No: 4E0 907 719 

   Component: Neigungssensor  H03 0020



1 Fault Found:

00892 - Switch for Trunk Closing Cylinder (F248) 

            007 - Short to Ground - Intermittent

             Freeze Frame:

                    Fault Status: 00100111

                    Fault Priority: 3

                    Fault Frequency: 9

                    Reset counter: 25

                    Mileage: 373302 km

                    Time Indication: 0

                    Date: 2017.11.02

                    Time: 09:22:08

Can you not trigger the lock using the side of a large screw driver? Does it latch? Does the striker plate move down an inch or so?

I know I have a D2 not a D3, but I've replaced my boot latch more than once due to (in my case) mostly microswitch problems (also broken nylon internals).

I certainly used the shaft of a screwdriver for testing locking and unlocking with the lid open, very useful trick. ;)

I don't know if the D3 latch is physically the same, but if it is swapping the microswitch is pretty easy and I have a couple of spare ones if it's the same.