Central locking system on 1996 900SE

Can anyone make any suggestions about a problem I am having with the central locking system on my 1996 900SE? (The car's dark green in color, for those who follow the Car Talk repair principles.)

The first symptom has been occurring for some time. Sometimes the passenger side front door will not lock when I turn the key in the driver's side door. Usually, if I turn the key all the way to the horizontal position, the button on the passenger side door will pop down, and the door will then lock. Last night, however, when I got into the car, unlocking the driver's side door had no effect on the locks on the other doors. I was very concerned about this, because this meant that the flap on the fuel filler also did not unlock (although I know there is some way to unlock it from inside the trunk). I got into the car, closed all the doors, and then pushed the driver's side lock button up and down, and that seemed to fix the problem--doubtless only temporarily.

Does anyone know how to fix this, or how much it might cost me to have it fixed?

Reply to
Kenneth S.
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There are two possibilities: the contact switch connected to the driver's side lock is worn and not contacting properly or there is some problem with the central lock controller located underneath the back seat. As you seem to be able to get the locks to work by messing with the key position, I'd be inclined to go with the door switch. Probably not too expensive from Saab, I'd guess $70-$100 as there are virtually no electronics inside. To replace just take the door panel off, probably a couple of screws and a linkage to remove. You can easily test it with an ohm meter, just figure out which pins on the electrical connector should be connected when the switch is engaged (both up AND down, two circuits) and test for continuity when the switch is operated.

Also check the lock controller (under back seat) connection to wiring harness... if it's loose it may give symptoms as you describe.

Mine turned out to be the lock controller, wasn't sending out a pulse of long enough duration to operate the lock motors inside the doors. Weirdly, the trunk still worked fine, every time. I picked up a used one at a junkyard for about $40.

Dave

Reply to
Dave

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