Coupe Factory alarm, again

AdrianH · 05-04-17, 02:07 PM

I've done a fair bit of digging around but can't find any previous posts pointing to an easy solution here. This is my daughter's B4 Coupe – the honky alarm and hazards are going off every time she opens the door. In these circumstances the central locking also fails to function. I'm not sure of the mode of operation of this crude alarm – I'm guessing it's activated as a slave function of the central locking pump –*is this correct? Or is it separate electrical circuit?

I tested the red/black feed at the drivers door central locking switch yesterday and got 12+ volts, and of course when I put it all together again all was fine, so I guessed –*incorrectly –*that it was just a dry connector. Obviously not however.

Also, where do I find the central locking pump in one of these cars – I'm guessing it's down on the offside of the boot like the B2.

msh · 05-04-17, 03:17 PM

In B4 era car the alarm is likely inside the central locking pump.

I don't know which central lock switch you tested - car with factory alarm should have two central lock switches - one in central lock cylinder, another in door lock, so that alarm could determine if the door has been unlocked with key or without.

mikes2 · 05-04-17, 04:37 PM

central locking pump is behind the side trim on the driver side rear. you need to remove the rear seats and B pillar trims plus the side panel to access

AdrianH · 05-04-17, 04:45 PM

Thanks guys.

I've only just out all that trim back after fixing the headlining... so hopefully I'll track down a broken wire or something.

msh · 06-04-17, 09:49 AM

Start with the wiring in drivers door, in the rubber boot; most likely place for some wire to break.

05-04-17, 04:37 PM	#3
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	central locking pump is behind the side trim on the driver side rear. you need to remove the rear seats and B pillar trims plus the side panel to access __________________ 1991 90 quattro 20v sport 1991 90 quattro

05-04-17, 03:17 PM	#2
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	In B4 era car the alarm is likely inside the central locking pump. I don't know which central lock switch you tested - car with factory alarm should have two central lock switches - one in central lock cylinder, another in door lock, so that alarm could determine if the door has been unlocked with key or without.

05-04-17, 04:45 PM	#4
AdrianH Grown up member Join Date: Jan 2014 Posts: 218	Thanks guys. I've only just out all that trim back after fixing the headlining... so hopefully I'll track down a broken wire or something.

06-04-17, 09:49 AM	#5
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	Start with the wiring in drivers door, in the rubber boot; most likely place for some wire to break.