I'm in the process of putting the guts back in my doors. My car originally had power locks, but the previous owner took the actuators out. I've finally got around to rebuilding the whole lock system. Today I replaced the pigtails on both sides. I hooked up both switches and both actuators, but when I hit the lock switches nothing happens. I checked with a test light and I have ground and power at both switches. I then tested the connector for the driver's side actuator and had power to one wire when pressing lock and the other when pressing unlock. I then checked the connector for the passenger side and have no power at either wire at the actuator. I'm not sure why the driver's side wouldn't work either though....?? Is there a chance the switches themselves are bad? They look a little corroded, but not too bad. Do these switches go bad? That's the only thing I can up with.

Anybody have any thoughts?

Thanks

 

Yes they do go bad, and if you have one bad switch, it can also prevent a good one from working.

Good luck... GUSTO

 

Thanks for the reply, maybe I'll order a couple of switches. The only thing is, if I'm getting power to the driver's actuator when I hit the switch shouldn't that one be working? I know the ground runs from the passenger door skin, through the passenger switch and over to the driver's side. The ground is making it through the passenger switch because I know I have ground at the driver's switch, so I don't see what the driver's side is missing. I know the passenger side is missing power, which it has at the passenger switch's connector, so the power must not be making it through the passenger switch to the actuator.

 

If I recall correctly, the driver's side operate the passenger side but a little corrosion will inhibit the connection from operating correctly. I went through this with my 78 a few years back...found one switch wire that was frayed while others corroded. It all has to be cleaned up. I also replaced both actuators...the rubber boots had deteriorated and moisture eroded the ability of the plunger to actuate the linkage and open/close door locks. Also...lube all those linkage rods.

Here's link to an article that illustrates how to troubleshoot Power door locks.

http://www.hunt4cleanair.net/Article...lockrepair.pdf

Hope this helps!

 

Thanks, that's a good read

I got to do a little more diagnosing today. I basically checked continuity of the entire circuit using my lectric limited wiring diagram. I knew the driver's side gets it's ground from the passenger side, but what I hadn't realized was the passenger's side actuator gets it's signal from the driver's side. There is no direct connection from the passenger switch to the passenger actuator.

That being said, I tested continuity for the two wires coming from the passenger switch over to the driver's switch (light blue and black) and they both checked out. I then tested the three wire harness (gray, orange, and tan) which feeds both sides. There is connector with these three color wires on each side, I had continuity from the harness' connector to each switch, and through the harness from the driver's side to the other. I then checked continuity from the driver's switch to the actuator, that was good. I then checked the connector on the passenger side kick panel where that three wire harness connects (orange, gray and tan... orange powers the switch, gray and tan go to the actuator) I checked the gray and tan wires from the connector to the actuator and found good continuity.

Next, I decided to check the switches. On the driver's side I had continuity from the post for the orange (power) wire to the post for the gray wire when I pressed the lock switch one way, and continuity from the orange post to the tan post when pressing the other way. The driver's switch looks pretty decent condition wise. I then did the same test on the other side, but I found a lot of resistance in the switch. My only thought is it has to be this switch, and that's affecting the whole system. I still don't understand why when pressing the driver's switch the driver's side doesn't at least work. I understand they're tied together, but I don't see how the passenger switch being bad could affect the driver's side. I could see if the driver's switch was bad how it would affect the passenger's side because the passenger's side receives it's signal via the driver's side, but the driver's side has everything it needs independently (power, ground, and a signal that's making it to the actuator when the driver's lock button is pressed).

Am I missing something? Should I just go ahead and try to replace the switches. I just hate throwing parts at things, I'd rather understand what's going on first.

 

 

Sounds pretty thorough to me. The thing is once the switch is bad...you can't get in there to take it apart and so it may be time to replace. It's like the actuators...once the boots go...it undermines the integrity of the unit. Unless you want to have to go back in...replace them.

I went through the same circuitry tests as you are but once I repaired the frayed wire, the switch worked fine. I was able to keep it wired up with door panels off and test all those connections until I was satisfied with the operations. I even cleaned the green corrosion off the switch contacts with emory paper and it improved the circuit connection and operation. So I stuck with what I had. I would say exhaust your options. If you don't get the performance you feel you need...then replace the switches!

 

Thanks. I had gutted the doors to replace old scratched glass, worn regulators and motors, missing lock actuators, and a worn latch assembly and outer handle.

As of now I have no response from either actuator, not even poor performance. I checked again and the resistance in the passenger side switch is between 2 ground posts, ground in to the passenger switch, and ground out to the driver's side. So maybe it is just a bad ground due to a bad passenger switch, but I am showing ground at the driver's switch so I thought I would at least get some function, if even just intermittent, but nothing!

I don't mind replacing the switches, I was just hoping to confirm it first. I can't come up with anything else though...

 

So I ordered 2 new switches. I think the passengers side is the only bad one, but for the price I figured might as well know they're both good. Hopefully this is the problem, because if not I'm out of ideas.

 

I wanted to update this for anybody that winds up with an issue like this down the road. My problem ended up being the switches, for the most part... I also ended up finding an issue with the wiring.

After installing the new switches the driver's side actuator worked pressing either the driver's switch or passenger's switch, but the passenger's side did not work at all. After some more testing I found the tan wire going to the passenger's actuator (theres 2 wires, tan and gray, for both actuators - one gets a 12v signal for unlock, the other for lock) was not getting a signal. This wire, along with the gray wire from the actuator, and the orange power wire from the passenger's switch, run back through the door to a 3 wire connector at the passenger's kick panel. From here, the 3 wires run to another 3 wire connector at the driver's kick panel, then into the driver's door where the tan and gray wires go to the driver's actuator(the driver's side has 2 gray and 2 tan wires, one pair goes to the driver's switch and one to the passenger's actuator), and the orange goes to the driver's switch for power. Once I determined this, I had a starting point for the tan wire.

Using a test light I found I had a signal in the tan wire from the driver's actuator to the first 3 wire connector at the driver's kick panel. From there I had a signal across the connector. Going over to the passenger's side I found NO signal in the tan wire at the 3 wire connector. I took the glove box out and the speedo/tach cluster out and opened up the loom that those three wires run through. I tested the tan wire in a few separate spots and found no signal. After those 3 wires leave the driver's side kick panel they join the harness and go behind the fuse block. As this was the only section of wire I couldn't really access, I'm guessing there may have been a break back there.

So, rather than continue to open up the factory harness and possibly have to pull the fuse block, I opted for a simpler solution. I tapped into the tan wire, prior to the driver's kick panel connector, where there was a good signal. I then ran the new wire up under the dash and over to the passenger's side kick panel where I fed it back into the tan wire. I soldered everything in and made it all look clean. Everything works perfectly now, and I'm pretty happy having figured it all out!! Now, onto installing my alarm/keyless entry!!

 

Good work! I doubt anyone will fault you for splicing in a new wire. The alternative--removing the main harness--is FAR from fun! Such does though make adding keyless entry/alarm easier.