fuel and alarm buttons stopped working

cheechy

A2OC Donor
Anyone know what fuse controls the interior alarm and fuel buttons?

Just went to fill up there and found the lights on both had gone out and they didn't work.

Managed to get to the fuel by the boot but could do with a pointer here!

Thanks
 
Anyone know what fuse controls the interior alarm and fuel buttons?

Just went to fill up there and found the lights on both had gone out and they didn't work.

Managed to get to the fuel by the boot but could do with a pointer here!

Thanks

It is more likely that your door microswitch has failed, so it is not registering the door as open and they ONLY light and work when the door registers that it is open.

Did it register as an open door on the dash when the driver's door was open?

Check out the "How To" Index section for help on this and other subjects.

Possible Door Lock Microswitch Fault Repair

Steve B
 
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Thanks Steve literally just happened so I've not had time for much in the way of diags.

Only out the door on a week ago or so so it may never have worked but never thought to check!
 
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Thanks Steve literally just happened so I've not five much in the way of diags.

Only out the door on a week ago or so so it may never have worked but never thought to check!

It is a very common fault, but if you are going to repair it yourself following the "how to" it should not cost much at all and not a nightmare job, you just need a fair bit of time (and somewhere warm to do it!!!

Steve B
 
Thanks Steve as always you are spot on. Checked the door open and alas the dash not registering the fact that the door is indeed open. Passenger door is fine!

Would be nice to get 2 weeks with this car when nothing is wrong with it but hey :cool:
 
Thanks Steve as always you are spot on. Checked the door open and alas the dash not registering the fact that the door is indeed open. Passenger door is fine!

Would be nice to get 2 weeks with this car when nothing is wrong with it but hey :cool:
The thing to remember is that once you have fixed these issues they really are quite a reliable car and won't rust away.

Plus the addiction for them gives you a sense of achievement when you have sorted everything out!

Onwards and Upwards.

Steve B
 
highly likely to be the solder joints and not the micro switches, please check BOTH whilst the lock assy is out, as its a bitch when you refit it all and find the problem is still there.
Ideally reflow the solder joint with LEADED solder a little electrical flux

Cheers,
Paul
 
highly likely to be the solder joints and not the micro switches, please check BOTH whilst the lock assy is out, as its a bitch when you refit it all and find the problem is still there.
Ideally reflow the solder joint with LEADED solder a little electrical flux

Cheers,
Paul

Thanks for the added info about the leaded solder Paul.

The link I posted above includes the recommendation to reflow the solder joints on the circuit board..

Matt posted a very detailed How To for this.

Steve B
 
My alternative fix method would be to remove the switch from my other front drivers door and then do a lazy repair when it suits :)
 
My alternative fix method would be to remove the switch from my other front drivers door and then do a lazy repair when it suits :)

good idea, but suggest reflowing and checking/cleaning the micro switch BEFORE you fit it, would be a PITA if you fitted it and then found it was faulty (vert common fault) and whilst it is off the reflow is a 10 min job


Cheers,
Paul

PS I now have matching rear bench seat :) :) :)
 
As always Paul you are right.

Its a shame that I've all the finesse and patience of a rabid skunk when it comes to using a soldering iron.

And good news on bench. Bet its not as clean as the fronts :p
 
Right ok so given I need to now fix at least one of the 2 drivers door microswitches i thought I'd start on the one that obviously isn't in the car just now.

Upon close examination of the back of the board it looks like this

IMG_20171115_191947.jpg

I'm guessing whilst its different to the pic this is as expected on later cars maybe?

Guessing i just have to melt through the resin and remove / replace solder droplets near the plug?

Assuming I dont have to rejoint the microswitches themselves?
 
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Right ok so given I need to now fix at least one of the 2 drivers door microswitches i thought I'd start on the one that obviously isn'tin the car just now.

Upon close examination of the back of the board it looks like this

View attachment 32364

I'm guessing whilst its different to the pic this is as expected on later cars maybe?

Guessing i just have to melt through the resin and remove / replace solder droplets near the plug?

Assuming I dont have to rejoint the microswitches themselves?

I am no expert at "electrickery" but that looks like it doesn't need resoldering to me.

Perhaps the microswitch itself is not working.

Have you access to a multimeter tot check that the switch is operating as it should?

Steve B
 
I am no expert at "electrickery" but that looks like it doesn't need resoldering to me.

Perhaps the microswitch itself is not working.

Have you access to a multimeter tot check that the switch is operating as it should?

Steve B

Oh no I'm not in the 10% again (Paul described to me that the fault was likely to be 90% bad solder / 10% microswitch) !

Yup I'll dig it out and go round..to me this looks like a board that was modified by Audi in later generations due to reported dry joints. But what do I know? :)
 
Ok just done a quick continuity test and I'm getting continuity on all switches from outside of each chip from the left sided pin (as per location in pic).

Alas I'm not a electronics whizz either - I know each of the switches clicks etc but not sure if that still means they work.

Anything else I should check for? I have a fairly decent budget multimeter but not a clue aside from continuity and testing batteries :p
 
Ok just done a quick continuity test and I'm getting continuity on all switches from outside of each chip from the left sided pin (as per location in pic).

Alas I'm not a electronics whizz either - I know each of the switches clicks etc but not sure if that still means they work.

Anything else I should check for? I have a fairly decent budget multimeter but not a clue aside from continuity and testing batteries :p

When you depress the switch the continuity should change (Open from closed or vice versa)

Steve B
 
ok so then I'm stumped - all 4 switches working?

Whats left to check??

It may have just been a poor connection, or corrosion on the connectors where these are plugged into, or in the door connector?

Or even just that the microswitch plunger was not connecting with the mechanism and so wasn''t being depressed.

I would reassemble and check all connectors and the plunger contact point.


Steve B
 
Was there not a reported case of failed microswitch where the connecting pin had worn down just a little so it wasn’t pushing the plunger in far enough?
Someone added a little extra plastic on the end and it was sorted. Just guessing.
The only microswitch I’ve repaired was on a washing machine and the multimeter showed no change between on and off - just a constant connection. New switch and done.


Sent from my iPhone using Tapatalk
 
ok so then I'm stumped - all 4 switches working?

Whats left to check??

Sorry just realised the one that detects the door opening (microswitch number 5!) might be the cookie

How do I do a proper non destructive test given I cant see wire or connectors exposed?
 
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