Central Locking Issue
Posted: Mon Mar 17, 2014 2:03 pm
I have had an issue with my central locking and I thought I would record my thoughts for posterity.
The Bongo is a 1999 model with factory central locking. In addition, I had a Thatcham locking/immobiliser fitted one year ago.
The issue (which began a couple of weeks ago) was that after locking the doors, the passenger, sliding, and tailgate locks would sporadically relock or reopen, often several times. I'd walk away and hear the doors clunking; usually they would settle down.
At first I suspected the relay under the glove compartment. After looking at the wiring diagrams posted in this forum, I realised that there were two signals coming from the driver door; W/B was at 12V on unlocked, and Y/R was at 12V on locked. By checking the voltage going into the relay it looked like the interruption to the voltage was coming from the driver door.
I took the driver door panel off and spent a good while waggling wires. The important wires come from an inaccessible switch built in to the door lock mechanism. This involved holding the door panel with one hand and poking around with the other. I decided to try disconnecting the panel with all its switches and plugs, and found (to my surprise) that all the locking still seemed to work.
It was at this point I realised that the keyswitch wires were going into the original factory remote locking system, which was taped to the inside of the door panel. The giveaway was the antenna. When I left it disconnected, things seemed much improved.
The situation at the moment is that I have put everything back with the factory remote central locking disconnected. I haven't re-experienced the original issue yet. I live in hope.
(Of course, having disturbed all the wiring in the door, I may be living in a fool's paradise, and the problem will return after about 15 potholes.)
The Bongo is a 1999 model with factory central locking. In addition, I had a Thatcham locking/immobiliser fitted one year ago.
The issue (which began a couple of weeks ago) was that after locking the doors, the passenger, sliding, and tailgate locks would sporadically relock or reopen, often several times. I'd walk away and hear the doors clunking; usually they would settle down.
At first I suspected the relay under the glove compartment. After looking at the wiring diagrams posted in this forum, I realised that there were two signals coming from the driver door; W/B was at 12V on unlocked, and Y/R was at 12V on locked. By checking the voltage going into the relay it looked like the interruption to the voltage was coming from the driver door.
I took the driver door panel off and spent a good while waggling wires. The important wires come from an inaccessible switch built in to the door lock mechanism. This involved holding the door panel with one hand and poking around with the other. I decided to try disconnecting the panel with all its switches and plugs, and found (to my surprise) that all the locking still seemed to work.
It was at this point I realised that the keyswitch wires were going into the original factory remote locking system, which was taped to the inside of the door panel. The giveaway was the antenna. When I left it disconnected, things seemed much improved.
The situation at the moment is that I have put everything back with the factory remote central locking disconnected. I haven't re-experienced the original issue yet. I live in hope.
(Of course, having disturbed all the wiring in the door, I may be living in a fool's paradise, and the problem will return after about 15 potholes.)