View Full Version : Help with power door locks... no power at pass. switch?

July 26th, 2004, 19:25
Alright, so today I finally decided to tear into my power door locks on my '87 laredo per the infamous "Greg Smith Power Door Lock Fix Writeup", but I'm hung up on one of the first steps. Greg says in his writeup to check for a full 12 volts at either the passenger side door switch, or the red/dark green/white connector in the passenger side kick panel.

I've poked and prodded with the voltmeter and I cannot find 12 volts here from either side at either the switch or the red/dark green/white connector. I tested the 30amp breaker in the fuse box by switching it with the power windows, seems to work fine there. So, I made a little jumper out of a piece of wire and stuck that in where the breaker for the power door locks goes, and I still have no voltage at the connector in the passenger kick panel, or at the switch.

Am I missing something here? Is there another fuse or relay somewhere that I'm missing for the power door locks? Should I just suck it up and run a new power wire with an inline fuse from the battery (I would rather not... :()

July 26th, 2004, 19:44
For giggles, I just hooked a hot lead directly from the battery and temp spliced it into the red wire on that 3 pin connector in the pass. kick panel, and was able to get the locks to work from the passenger side switch, but not the driver's side. I assume there must be another wire to splice somewhere in there to make the driver's side switch work, right? I'm pondering just running a new hot wire from the battery and putting a fuse in, but only if I can make it work on both switches without a bunch of work.


July 26th, 2004, 19:46
what i have seen often is the wiring under the carpet under the driver's foot area usually gets moisture and corrodes. check for broken wiring there.

July 26th, 2004, 20:15
Did you turn the key to the on position when checking for voltage?

July 26th, 2004, 20:24
Yeah, I had it turned to on the whole time, but the power locks should work either way.

Anyway, I'll dig into the wiring under the carpet tomorrow... hopefully that won't be the case, but you may be right, as the driver's side switch won't work even when I hook a hot lead to the pass. switch. The driver's door did however unlock and lock from the passenger switch, so who knows.

July 27th, 2004, 03:44
before you go and dig into some complicated repair, pull the carpet up under the driver's foot area and check the wiring between the kick panel and the trans tunnel.

Greg Smith
July 27th, 2004, 05:56
Of course you only get voltage on the white and green wires comming out of the master switch when you are pushing the lock or unlock button. The red incomming wire into that switch and going into the passenger door switch and going into the two existing keyless opener relays in the passenger kick panel if you have them should be hot at all times. You should have 12 volts on both sides of the 30 amp breaker in the fuse panel also. Your power wire to the master switch goes straight from the fuse panel and does not go under the carpet IIRC. If your locks are working a little or trying to work you are getting voltage the question is how much. If you had a short the breaker would be trigger and no voltage would be there and the locks would not be trying to work at all. Greg

July 27th, 2004, 18:39
Alright, I found it, but not before frying my driver's side switch. Now I have unlock, but no lock (due to the fried driver's switch) If only I'd looked at the wiring diagram before I started futzing around with 12 volts. :|

The locks were not working at all, and I had 0 voltage on any of the wires in the passenger kick panel, but I did have voltage at the fuse panel. After I fried the driver's side switch, I started poking around. Mine is a Laredo model with no keyless entry, and no power seats, but the harness for the power windows and power locks does run under the carpet. On the driver's side it wraps around under the carpet near the seat, and back up towards the firewall. After that it goes across and straight to the passenger side kick panel. I can only assume this is for providing power to the power seats in the limited model.

Anyway, under the carpet on the driver's side there was (keyword: was) a splice where the wiring came out of the fuse panel and then split off to the driver's side kick panel, then went into the harness over to the passenger side kick panel. This "splice" (I'm assuming, because there was nothing left of it), was completely corroded and none of the wires were even touching anymore. The main power wire coming from the fuse box was nothing but corrosion for about an inch from the end. I cleaned the wires up and re-spliced them back together with a solder gun and now I have power where I need it. The locks are pretty sluggish (only unlock right now), because I haven't added in the relays.

Anyway, after all that, anybody have a driver's side power door lock switch assembly to sell me? :)