Strange power lock issue

[WhiskeyFoxTrot]

Power locks were working fine in my 91 lx…… now all of a sudden the drivers door switch is not working at all, and the passenger side switch will only unlock both doors, but won’t lock, it clicks like it wants to but won’t lock…… any ideas where to start? Thanx

 

[Noobz347]

Pull the door switches [carefully] clean the contacts and reinstall.

If it's still not working:

Pull the door panels, locate the door lock actuators, clean, lubricate, and reinstall.

 

[General karthief]

Can you manually lock/unlock the doors?

 

[ChaseRoads]

Get out your meter and start checking for a short between wires. I bet some wires in the door elbow finally wore out

 

[WhiskeyFoxTrot]

Ok, so there’s power at the switch, I. Leaned all the connection points, they seem fine, I pulled the door panel and probed actuator wires, I have power to one wire when hitting lock

 

[WhiskeyFoxTrot]

Actuator bad? If I manually lock both doors and hit unlock on passenger side both doors will unlock

 

[ChaseRoads]

Give this a read.

Electrical - Power door lock troubleshooting Foxbody

Ok. Edit with details on what does what and how to check it. It starts on the drivers side. A black with white stripe power wire. Constant ground from the circuit breaker (metal box) on the starter relay. If it does not have 12v check the cb and wires for a short. 2 black ground wires that...

stangnet.com

 

[WhiskeyFoxTrot]

Ok, so I looked through that thread, if I jump pink/green on driver side to pink/green on pass side and same with pink/yellow, the door locks work as should……. Should I just run new wire from switch to switch and splice in?

 

[WhiskeyFoxTrot]

Or would you try to locate the short? Wires are so tucked and taped, what’s the lesser of the evils?

 

[Noobz347]

I would shoot the wires with a meter. I am not convinced that it's a broken wire. More often than not, it's corroded switch contacts.

The good part is that you know your actuators are good

Can you get all the locks to cooperate when you jump the posts on the back of the switch? If so...

 

[WhiskeyFoxTrot]

I replaced both side with new switches, there’s an old alarm, plus a dealer installed keyless entry, the keyless entry coincidently stopped working about a month ago, i might just take it to a auto alarm installer to have them rip the old stuff and see …. Way above my skill level

 

[AeroCoupe]

So there is an aftermarket alarm and an aftermarket keyless entry? If so just remove them both yourself. I was in the home and car audio business years ago and installing these could be a bit tedious due to needing to know what wires to tap for the function intended but uninstalling one is just follow the wires and remove them at the point they tap any factory wires. Take your time and be sure to tape or heat shrink any locations where the jacketing on the wiring harness is compromised i.e. scotchloc connectors or removed jacketing for soldering. If they cut the wiring harness then just repair it as needed. My bet is removing them will solve your problem(s).

 

[ChaseRoads]

Before I run completely new wires I would find where the door harness plugs into kick panel harness. One at a time I would check each wire for a short to ground , and maybe even use a jumper wire and jump out the connection at the switch to the kick panel harness. One or two of those wires are shorted inside the door . Once you find what wire let’s it work when jumped, you know what wire to replace.

 

[AeroCoupe]

Pull the alarm and keyless entry and repair any wiring damaged from them. With them installed there are just too many variables and removing them cleans things up to trouble shoot. By no means am I saying not to install an alarm as my Coupe has had the same one for over 20 years and it still functions as intended and all I have had to do is replace a remote battery here and there.

Once they have been removed and if the locks still do not function then you can trouble shoot using the traditional methods.