OEM Remote Central Locking Troubleshooting

[Colesy]

Does anyone know how to troubleshoot OEM remote central locking?

I have fobs as below:

They both work to the point that I press the button and the light comes on on the fob.

I think the control unit is 998 VAG 151 which I have found under the dash, does anyone have a wiring diagram?

Also the central locking isn't unlocking with a key from the drivers door, does anyone know what might be causing this? The central locking still locks with the key just doesn't unlock. So I would guess it is something inside the door that needs attention.

Thanks in advance for any help.

[UrS4boy]

We're not psychic. You have to tell us what the patient is. B3 Coupe, B4 avant, etc.? Infrared or radio frequency??

The central locking control module and pump is under the seat of a C4 and in a right rear cavity of a B3 Coupe.

Here is an example C4 central locking control module wiring diagram (IR remote in this case):

[Colesy]

B4 S2 coupe. It was the wiring diagram of the "998 VAG 151" I was after which I thought was fairly specific, it seems to be fitted to various models. I don't know whether the alarm is IR or radio.

Thanks for the above though. The central locking switch or wiring to it will have to be checked over.

[Colesy]

So resetting the alarm unit has fixed the door key central locking problem!

But it would still be good to get the remote central locking working. All the wires look to be connected up apart from the one in the photo below:


I assume this connector would go to the IR (or other) sensors for the remotes? It would be good to know what these look like so I can find them, does anyone have any ideas?

[UrS4boy]

This 998 VAG 151 is aftermarket, not OE per se.

Here is a diagram that might work for you:

[UrS4boy]

Read this:

http://www.audifans.net/ftopicp-25290.html

[S2central.net]

The correct schematic for MY96 Coupe to start with should be this one - http://www.s2central.com/S2_Schematics/E/E23.pdf
Then compare with the option with factory fitted infra-red remote locking - http://www.s2central.com/S2_Schematics/E/E29.pdf

The pump unit is V94... I expect that retrofit unit you have was an aftermarket / dealer fitted item which brings its own radio receiver module and connects into V94 to tell it when to pump/open or suck/close the doors. My S2 has something very similar fitted - possibly 'quantum' branded - I cannot remember where the wiring info is for that, but it will be getting unpicked at some stage.