Sierra 1991 Central Locking Problem

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Tue 4 Apr 2006 22:06
Sierra 1991 Central Locking Problem - wrightyl
Hello,

I own a 1991 Sierra 1.8LX on a J plate.

When i pressed the keyfob to open the car the other morning the central locking started to lock/unlock the doors continuously, and the only way to stop this was to take the fuse out. Have changed to the spare keyfob and this does the same thing, the doors just lock/unlock themselves over and over again till you take the fuse out. I have checked the connections to the central locking by taking the door panels off the doors, and they appear to be ok. I have looked in the Haynes manual for my Sierra and I thought it might be a relay, but the model on this year does not have one for the central locking, so i've ruled that one out as well. I haven't had time to check this but i thought the problem could possibly be with the central locking control unit (if it has one)? Does anyone have any ideas, or had a similar problem?

Any help would be appreciated!!

Thanks

Wrighty
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Tue 4 Apr 2006 22:14
Sierra 1991 Central Locking Problem - bell boy
I would say one of your door lock mechanisms has gone doolaly and fooling the system into thinking a door is a jar
could be any of them but for some reason on fiesta"s it was front passenger
--
\"a little man in a big world/\"
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Tue 4 Apr 2006 22:22
Sierra 1991 Central Locking Problem - wrightyl
Hello ta for the reply

Do you mean the actual barrel lock itself? on either drivers or passenger door? The key doesn't lock the passenger door that well, but its ok on the drivers door, so possibly the barrel might need replacing on that side?

Thanks
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Tue 4 Apr 2006 22:45
Sierra 1991 Central Locking Problem - Civic8
Drivers door will be master solenoid so it will more than likely be that.
if both passenger and drivers door are master, ie operated by key on both sides locks the doors, they are both masters,could be either one failed...ie if passenger side will only lock that door with key.. master is drivers door only and will be playing up used to be common fault
--
Steve
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Tue 4 Apr 2006 23:00
Sierra 1991 Central Locking Problem - wrightyl
Cheers Steve,

Will check that one out next, both sides lock all doors.
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Wed 5 Apr 2006 09:06
Sierra 1991 Central Locking Problem - jc2
The door lock/unlock cycle is usually triggered by a "door ajar" signal;check the microswitches in the lock assemblies.
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Wed 5 Apr 2006 13:17
Sierra 1991 Central Locking Problem - IanJohnson
We had a 1990 Sierra 1.8GLX (bought 2nd hand in 1993 and sold in 1997) that did this to me once.

I was leaving work one night and when I unlocked it away it went...

Took a chance and opened a door which stopped it. Couldn't work out what caused it and it never happened again.

Investigation showed that the driver's door microswitch was not working (had not worked since we got the car as the central locking did not work from the passenger door - system sensed door open so would not lock but would work from drivers door (over-rides local door open switch, changing the switch didn't make any difference as the first time the door was closed it broke in the same way as the original. All this is a red herring anyway as it did not seem to cause the lock/unlock/lock/unlock cycle.
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