wicked96

I know this is a worn out subject but I have a fairly strange condition with this 82 Vette.

The door lock actuators work for lock wont work for unlock.. unless I ground the grey wire from the drivers side switch! My test light will faintly light up on the gray wire when grounded and the switch in unlock position. So it is not full 12 volts when I do this. It is full 12 volts when not grounded on the multimeter!

If I test the switch terminals I have power on the grey wire for lock and unlock. This is a polarity switching circuit I believe since you must energize the actuator in each direction for lock or unlock. Grey wire lock and Tan wire unlock. So one has to be hot and the other ground to complete a circuit then reverse polarity to reverse direction.

I have power and grounds to all the correct places except the grey wire stays hot in both switch positions. I believe the grey wire has to switch to ground in the switch when you switch to unlock. This would then point to a bad switch. Anyone know if this is a symtom of a defective switch? Am I correct or at least on the right track?

Thanks!

hugie82

If you car hasn't been bubba wired usually the switch or the plug going to the switch is shorting. Either side can cause freaky things to happen. They sell pigtails for the wires and plug. The switches are gm standard and can be bench tested.

74 LS4-454

I also have a similar problem with the door locks on my 82, will be watching this thread closely.
Both of my door panels are still off, so I do have easy access. It seems at times the when I use the inside switches, sometimes they don't have enough power to fully engage the locks to unlock. I have replaced both pigtails and the ground wire is attached on the passenger side door. and have also replaced the switches and replaced the DS switch again. I also have a hard time using the key on the DS door.
Anxious to hear how you correct your problem with the locks.

Arkyvette

I just closed up my 82 door panels. discovered that one of my door latches is separating. They are crimped/smashed together and one of mine had come loose at the top to the point that the lock arm was binding on the spring. I need to replace the entire latch now to get the locks working again, but I also need to replace that entire door due to a crack, so I will look for one with a good latch already in it. Getting in this area for long will make you invent new cuss words. I don't know if this is your problem and even with it unhooked there is quite a bit of force needed to overcome the power lock motor, but just one more thing to check out while your in there. FWIW, I changed out several lock motors in my old 95 suburban because they were weak and new motors cured it.

hugie82

SSROADSTER, you have to clean the lock actuators and oil all the moving parts. Then work the locks 50 times or so and they usually loosen up. Mine did

SIXFOOTER

The switches are usually suspect if the harnesses in the doors have not been hacked.
Your correct, it is a polarity switching circuit. It uses the same ground for both paths and the same wires, only difference is the contacts in the switch. You might be able to take it apart and fix it but I have never been able to get one apart and back together with any long term longevity.

wicked96

Thanks to everyone for the help!

I cleaned all the connections and repaired frayed wires in the pigtails without any improvement. So I changed out the switches and the harness pigtails on both doors. My issue was in the right door switch. I replaced the left side parts (in poor shape) and had the same issue. Changed the right switch (looked better than left) and presto! door locks worked. If you do this repair my suggestion is do not just crimp solderless connectors on the harness. You need full voltage through these connections. Solder the new pigtail into the harness.

ssroadster: with a test light you should see the polarity change at the actuator when you change the switch position. If not you either have a bad ground or switch most likely. Did you solder the harness repair you made? You have to oil all moving parts in the latch and the linkage to free it up.

Hope this helps! These electrical gremlins can really get to you!

74 LS4-454

I replaced both actuators, as my originals were shot......


will have to get the test light out.....my main problem seems to be that if I use the passenger and or driver's side switch, sometimes it doesn't have enough power to fully unlock the doors. the lock rod moves, but only slightly. There are times when I operate the switches and it locks or unlocks with force. Both switches were replaced, and then I replaced the driver's side switch again and it worked well for awhile. Going to change the passenger side switch again. It just feels like I don't get the full voltage each time. When I do get full voltage, you can really hear them lock and unlock. Again, both pigtails were replaced as they were both cut when the door panels were removed. Ground wire is attached to the passenger door.
Thanks for the tips.....glad you got yours working again........Tom

79vetter

Tom, I have the exact same problem as you except that most of the time I don't get the full voltage. Curious to the fix.

74 LS4-454

and I thought I was the only one.... yes I am curious for the fix myself.
I still have both door panels off, and the screw driver in the car, to open the driver's side door when needed.
It just doesn't get that full jolt all of the time. At one time I thought maybe the car needs to be running to get full voltage, but that wasn't the case. Appartently there must be a wire or these switches (which are cheapy made IMO) are not making the correct contact to get full voltage each time. On one of the switches I had in there, one of the poles was loose and that was the end of that switch.
Will keep you posted if I make any progress.

wicked96

Try a jumper wire right from the positive battery post to the orange wire at the switch. If it is an amperage problem in the harness your actuators will work perfectly with the jumper. I would cut the orange wire in a spot thats easy to put it back together (like the original harness repair) so I got a true indication of the power difference.

calwldlife

where can I buy the pigtails?

74 LS4-454

mostly all of the Corvette vendors sell them, and I am sure you can order from your local auto stores.....
ask for "78-82 Power Door Lock Switch Pigtail" around $15-$17 a piece seems to be the going rate......