C3 Power Door Locks
Thread Starter
Advanced
Joined: May 2016
Posts: 95
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From: Tolland Massachusetts
C3 Power Door Locks
When I bought my used 1979 C3, the power door locks would only lock the driver's door but not the passengers. The passenger lock post went down partway but did not fully engage. We pulled the door panels, cleaned out 49 years of crud and greased the pivot points. We also replaced the actuator. Checking the power, it seems the correct power is coming to the actuator. The same problem is still there, the passenger door still doesn't lock when the switch is pressed. I'm out of ideas and would appreciate any advice and suggestions. Thank you in advance for your help
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Joined: May 2016
Posts: 95
Likes: 7
From: Tolland Massachusetts
,
You can lock the passenger door by pressing the lock post down. Also, you can lock and unlock it with the door key. It tales quite a bit of effort to twist the key. I'm afraid the key will snap off. I hope you can give me some ideas. Thank you for your interest. Phil
You can lock the passenger door by pressing the lock post down. Also, you can lock and unlock it with the door key. It tales quite a bit of effort to twist the key. I'm afraid the key will snap off. I hope you can give me some ideas. Thank you for your interest. Phil
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i would say the linkage is binding or all crudy, maybe disconnect the linkage to the key and **** and see if it will work
Race Director
Joined: Mar 2017
Posts: 11,949
Likes: 4,507
From: Virginia
I had the same problem in my 79, did what you did, and it worked. Did you test the actuator before installing? I found that a gunked up actuator was the critical failure. The new one, a Wells/Airtex from RockAuto, was very smooth and actuated freely when manually operated.
Also, I think both switches need to be connected to test function before putting the door panel back on.
Also, I think both switches need to be connected to test function before putting the door panel back on.
Intermediate
Joined: Aug 2018
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It sounds like the lock mechanism on the door latch it gummed up. It was also greased with the same gunk at the factory. Take off the lock linkage at the latch and see if it freely at the latch and then on the linkage side
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Joined: Apr 2009
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From: Charlotte NC
BOTH switches need to be installed and in GOOD working order to get the system to work. I have encountered so many bad wiring connectors where the wires are broken off or just about to break off.
For what it is worth....the TWO wires that go to the actuator will SWITCH currents when you press the switch. So...for example. when you press down on the switch...the brown wire will be positive and the tan wire will be negative. And when you press up on the switch they reverse polarity.
I can say that I buy my actuators from DORMAN and use them due to they are very fluid and it will not cause for excessive effort while turning the door key to lock and unlock the door. I have used the AC Delco actuators but I have to physically feel them before I buy them and I have to go through about ten of them before I can find one good one that the plunger in the actually will move with very little effort.
DUB
For what it is worth....the TWO wires that go to the actuator will SWITCH currents when you press the switch. So...for example. when you press down on the switch...the brown wire will be positive and the tan wire will be negative. And when you press up on the switch they reverse polarity.
I can say that I buy my actuators from DORMAN and use them due to they are very fluid and it will not cause for excessive effort while turning the door key to lock and unlock the door. I have used the AC Delco actuators but I have to physically feel them before I buy them and I have to go through about ten of them before I can find one good one that the plunger in the actually will move with very little effort.
DUB
Last edited by DUB; Aug 27, 2018 at 09:19 AM.
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Drifting
Joined: Jul 2005
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From: The Netherlands
I was away for the weekend, but I too had to clean up the insides of my door before anything would work properly again. This can be a pain: I advise small hands and a magnet pickup tool.
Le Mans Master
Joined: Sep 2002
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From: Myrtle Beach SC
When I bought my used 1979 C3, the power door locks would only lock the driver's door but not the passengers. The passenger lock post went down partway but did not fully engage. We pulled the door panels, cleaned out 49 years of crud and greased the pivot points. We also replaced the actuator. Checking the power, it seems the correct power is coming to the actuator. The same problem is still there, the passenger door still doesn't lock when the switch is pressed. I'm out of ideas and would appreciate any advice and suggestions. Thank you in advance for your help
http://www.hunt4cleanair.net/Article...lockrepair.pdf
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Joined: May 2016
Posts: 95
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From: Tolland Massachusetts
Thank you" huntforcleanair, that article brought together many of the ideas that other forum members shared. The passenger-side actuator is a replacement and we are getting a new one sent to us. One big clue from the article is that when I insert the key in the passenger door to open it, there is no assertive click . Actually turning the key takes some effort and mskes me afraid it might snap it off. Thanks to everyone for their help and comments.
Last edited by Philgran; Sep 1, 2018 at 07:17 AM. Reason: Misspelling
Thread Starter
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Joined: May 2016
Posts: 95
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From: Tolland Massachusetts
I’ve managed to get the 1979 power locks working. The other day, the power window on the driver side stopped working. Believing it was probably the switch, I pried up the console cover by removing the four screws and replaced the switch. Driver power window now working. However, the power locks and courtesy lights are no longer working. Is there a connector in the transmission tunnel area, I might have accidentally unplugged?
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I’ve managed to get the 1979 power locks working. The other day, the power window on the driver side stopped working. Believing it was probably the switch, I pried up the console cover by removing the four screws and replaced the switch. Driver power window now working. However, the power locks and courtesy lights are no longer working. Is there a connector in the transmission tunnel area, I might have accidentally unplugged?