Monday, January 21, 2019

Repairing fuel tank cap on Audi A4 B8

When I had the VCDS USB cable hooked up to the car to diagnose the cabin blower error, I came across a second issue. The VCDS software was reporting that the lock for the fuel cap was acting up. A print out of the error was as follows:

Address 46: Central Conv. (J393)       Labels: 8K0-907-064-46.clb
   Part No SW: 8K0 907 064 A    HW: 8K0 907 064 A
   Component: BCM2 1.1      H70 0134  
   Revision: 00002001    Serial number: 010967865308    
   Coding: 0100062000390040012001
   Shop #: WSC 06325 000 00000
   VCID: 2E4A198B2017BC72BDAC28D-807B

3 Faults Found:
02615 - Fuel Tank Cap; Lock 
            009 - Open or Short to Ground
             Freeze Frame:
                    Fault Status: 01101001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 128
                    Mileage: 264877 km
                    Time Indication: 0
                    Date: 2018.12.28
                    Time: 22:48:18

02616 - Fuel Tank Cap; Unlock 
            009 - Open or Short to Ground
             Freeze Frame:
                    Fault Status: 01101001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 128
                    Mileage: 264877 km
                    Time Indication: 0
                    Date: 2018.12.28
                    Time: 22:51:58

It appears thtat the fuel cap was not locking itself. Not really a problem, I mean, who siphons fuel to steal it these days. But it would be good to repair it nonetheless. I needed to have a look at the fuel cap lock to see what was wrong. If you open the cap, you will see a single screw that you can remove on the plastic panel.

Once this is done, using a spudger or blunt knife, remove the plastic panel. You will see the lock module on the left (model 8K0 862153 F). Slide this to the right and lift it out. It will be connected by a red plastic cable. Unclip this on the module side. Now you can remove it from the car.



If you are replacing the module, you can just follow the instructions in reverse to put it back in. I opened by module to see what the issue was. There are clips around the perimeter of the module.

Unclip these and remove the cover. Inside is a motor and lock mechanism.

To remove the motor, pull out the two pins in the plug (like above, with a needle nosed pliers) . Then you can wiggle the motor out of the module housing. I removed the motor and attempted to spin it with a 12 v power supply. I would spin, but only after a push. Monitoring the power supply, I notices that it current limiting was it was pulling more than 2 amps at certain angles of the armature. This is a sign that the coil was shorted or burnt out.

I doubt that I would be able to get a similiar motor, and it would be a pain to remove the gear and put it onto a new one, so I just bought a replacement module for about 30e.




1 comment:

  1. So, you can change the title to "REPAIRING THE FUEL TANK CAP ON AUDI A4 B8 FAILED" 😁😁😁

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