I bought a 2000 X facelift Passat last year and was told the remote central locking didn't work after the "alarm box" was replaced. I scanned it at the time and no faults were showing so I bought it. I thought I'd spend a weekend looking into the remote central locking at some point. Nearly 12 months later I'm now looking into it!
It's the 130 1.9PD - mapped to 178bhp, with nice big brakes on. It's a pleasure to drive and as someone who's had MK4 & 5 Golfs, a B5 Passat and a Bora Highline - it's the most fun. SE trim.
So to the fault. If I use the key in the drivers door to unlock, it unlocks the drivers door first then all the rest (pretty standard) however the red light remains flashing and the alarm will go off unless I put the key in the ignition and turn the electrics on. The red light stops flashing and I can then open the other doors. If I open any other doors before I've turned the key, the alarm will sound.
I was given two keys with the car, a battered old one and a new one. Neither key works remotely but both unlock the door and disable the alarm/immobiliser. I have tried the VW key pairing as listed in the manual, and I have tried increasing key count with VCDS - but that didn't work.
Today I had the CCM out and it was dry. There are signs of previous wiring repair but an hour's inspection of what I could get my hands on wiring wise showed no damage.
So, does anyone know what I can try next? VCDS reads the CCM and outputs show it seeing windows opening, door locks. Wing mirror switch location/heater etc.
Could anyone explain how the remote central locking works? Where is the receiver and what wiring goes where to take that signal to the ECU to receive and unlock. Secondly, could the car have had a new CCM (pics below) and it just be coded wrong? Thirdly, can I code it myself or is it a specialist job?
Pics below.
Thanks.