abarr_

I know it has been discussed, but there’s an issue that I haven’t seen:

- the central locking mechanism stopped working the other day. Came here, read some posts, disconnected the locking box, changed the fuse (even though original was not blown), noticed a ticking noise, reconnected and it started working again. I could lock/unlock with switch in central console, and pressing the alarm fob lock/unlock car.

- A few days after it stopped working again. Repeated the operation, it worked again, but instead of operational for a few days, today it just worked for a few moments.

- Fuse is fine. No signs of short circuits / burnt stuff anywhere. Alarm is triggered when corresponding locking button is pressed on fob and door is opened. Alarm is off upon pressing corresponding off button in fob.

Could it be that the central locking mechanism has become defective? Is there any other issue that could be producing this erratic behaviour?

Would appreciate comments.

Added later:

- disconnecting and reconnecting central lock unit doesn’t produce the ticking noise it used to produce any longer.

- little light above ignition key no longer on.

- central console lock switch doesn’t do anything.

- alarm works as normal.

pp000830

Hi Abarr,
Sounds like an intermittent connection problem, consider the following:
Make sure the car battery is charged and measures above 12.5 volts.
Purchase some spray electronic cleaner pull the fuse and hose down its socket with it.
Do the below with the car battery disconnected.
--Unplug the radio fob module under the seat and spray out its plug and socket.
--Do the same with the Motronic DME controller.
--Unplug the clock and spray the plug and socket on the back.
Also, solder joints in the clock are known failure points so if the above doesn't resolve the issue the clock can be disassembled and the solder joints on the circuit board can be reheated.
Related topics:
https://993servicerepair.blogspot.co...out-drama.html
See the very bottom of this page:
https://993servicerepair.blogspot.co...ing-light.html
How to service the immobalizer/remote fob module:
https://993servicerepair.blogspot.co...stance-of.html

Let us know of your progress with this issue.
Andy

carboy2

I had SunTek ceramic 70% (near clear) window film applied to the side and rear windows to reduce heat gain. I think this might be making central locking more difficult for me. Anyone else experience this?

abarr_

Thanks so much Andy. As it happens, I was tempted to email you after reading some of your blogs.

Will try your suggestions and revert back when I’m done.

abarr_

Update: took lock control unit out > took fuse out > cleaned everything as suggested > placed fuse back > measured battery voltage (12.8) > measured the black connector to the lock control unit (similar voltage to battery in some pins, zero in others) > reconnected unit > while no ticking noise I noticed immediately light above key in dashboard light up > pressed button in central console locks locked / unlocked > pressed button in alarm fob to cycle circuit and locks sounded as normal on both doors.

Then I went for a short ride, noticed the light in front of central console locking button light up, mechanism working as intended. Parked, got out, pressed lock button on alarm fob and both doors locked after the normal five flashes of turn lights.

No idea of reason of this erratic behaviour still… did not disconnect battery nor did I do the radio, motronic, clock steps. Will keep monitoring and if problem persists will then do those. Obviously the unit and the solenoids are fine.