Hey all -
Got a question for you. The central locking on my '87 cabrio has worked since I bought the car around 5 years ago. A few months into ownership I installed an ebay keyless system wired to the trunk lock actuator powered from the power antenna circuit.
About a week ago the car wouldn't unlock with the keyless. I replaced the batteries and played around with the locks and learned the following:
- the central locking always locks and unlocks from both drivers doors
- the central locking always locks from the trunk
- the central locking sometimes unlocks from the trunk
- the trunk lock itself is locking/unlocking as it should, it's just not communicating to the rest of the system for the unlock function
- same symptoms from the keyless as well as using the key in the trunk lock (except of course with the keyless nothing unlocks)
- same symptoms with power antenna fuse 28 pulled (no power to keyless unit)
- using the key in another lock allows the trunk lock (and keyless) to briefly unlock the car (until it stops working again)
- when locked from the trunk, the car will unlock itself after a random period of time. I've locked the car from the door tonight to test this.
I replaced the trunk lock actuator with another, thinking that the problem could be that the actuator is unable to talk to the central lock unit. The "new" one (same part no.) made no difference.
I've read up on the fuse located inside the central lock unit that blows etc, but it seems like that would cause the whole system to fail.
My hope is that there's a bit of 30 year old german solder that may have worked its way loose in the central lock unit somewhere. But before I go finding one of those, my next step is to remove the trunk lining and unplug the keyless unit to try and isolate it, assuming the PCB solder (or whatever tf) could be bad there instead.
Of course I don't want to trace wires but if I have to, any ideas where to start? I've only found one thread with symptoms similar to mine here but no solution was posted.
Any ideas?
Got a question for you. The central locking on my '87 cabrio has worked since I bought the car around 5 years ago. A few months into ownership I installed an ebay keyless system wired to the trunk lock actuator powered from the power antenna circuit.
About a week ago the car wouldn't unlock with the keyless. I replaced the batteries and played around with the locks and learned the following:
- the central locking always locks and unlocks from both drivers doors
- the central locking always locks from the trunk
- the central locking sometimes unlocks from the trunk
- the trunk lock itself is locking/unlocking as it should, it's just not communicating to the rest of the system for the unlock function
- same symptoms from the keyless as well as using the key in the trunk lock (except of course with the keyless nothing unlocks)
- same symptoms with power antenna fuse 28 pulled (no power to keyless unit)
- using the key in another lock allows the trunk lock (and keyless) to briefly unlock the car (until it stops working again)
- when locked from the trunk, the car will unlock itself after a random period of time. I've locked the car from the door tonight to test this.
I replaced the trunk lock actuator with another, thinking that the problem could be that the actuator is unable to talk to the central lock unit. The "new" one (same part no.) made no difference.
I've read up on the fuse located inside the central lock unit that blows etc, but it seems like that would cause the whole system to fail.
My hope is that there's a bit of 30 year old german solder that may have worked its way loose in the central lock unit somewhere. But before I go finding one of those, my next step is to remove the trunk lining and unplug the keyless unit to try and isolate it, assuming the PCB solder (or whatever tf) could be bad there instead.
Of course I don't want to trace wires but if I have to, any ideas where to start? I've only found one thread with symptoms similar to mine here but no solution was posted.
Any ideas?
