: Intermittent LH Power Door Lock Operation -- 91 Eldorado

10-03-10, 06:24 PM

The LH door lock actuator on my 1991 Eldorado operates intermittently with either the remote or the LH interior switch. The LH switch will, however, reliably operate the RH actuator, which also operates properly in response to either its door switch or the remote.

Incidentally, the RH actuator does not engage the linkage that is part of the RH lock/unlock mechanism, but I suspect that is an unrelated problem involving the linkage (I have not pulled the RH door panel see why).

I have pulled the LH panel, and the linkage to unlock the door operates properly, but only manually or when the LH actuator decides to work. The power connector to the actuator seems OK, the door key will physically unlock either door, and the anti-theft system logic is working properly.

The service manual shows that both actuators (which the manual refers to, BTW, as a "lock actuator motor") go through a lock/unlock relay, so I have two questions: first, could that relay operate intermittently for just one door (since the LH actuator is not completely dead), and thereby be the problem; and second, if not, then is there anything I'm missing in suspecting it's just a bad LH actuator motor?

Thanks for any help.

11-06-10, 02:09 PM
I would strongly suspect first that the actuator is faulty.
Since you get the same results from the RKE and / or LH switch I would suspect that the actuator is either sticking or failing.
I must assume that the key will effortlessly open and close the lock.
I must assume also that the wire harness has no obvious abrasions or non factory splice / connections.