1969 Mark III Electrical Issues

Hi Bill,
I appreciate all you do to support Lincoln owners! I have a problem with my ’69 Mark III. I purchased the car four years ago. A previous owner had disconnected the passenger side window motor from the original wiring and installed his own toggle switch and wiring. He installed it the dash ashtray where the lighter used to be. Pretty crazy but it worked!
I recently had a need to replace the front passenger side glass and decided to try to get the power window functioning with the original wiring and switches. I reconnected the motor to the original wiring. Not to surprising to see that the window would not operate with the door switches. I started pushing and pulling on various connectors. Low and behold, when I squeezed the window motor connector the motor worked using the door switches (driver and passenger switches). I unplugged the connected and adjusted the make and female connectors to improve the connection. Without squeezing the connector the window continued to function.
Once I had everything back together it no longer worked. I removed the metal trim from the door pad and wiggled the switch wires and the switch connector. Window was once again working!
Now I occasionally have a condition when it stops working. The drivers side window is also acting up but not as often. When I operate the power window switches (when the motors are not working) I do hear a click and I are the interior lights dim. I am wondering if this could all be related to a bad relay or a bad ground some where? When working, the motors raise and lower the windows quickly so they appear to be good.
Any ideas?
Thanks,
Brent
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Hi Brent –
There are many things that can go wrong with power windows. You have already identified one of them. Why not repair all of those bad connections first instead of wiggling wires and hoping.
We have the wiring diagram available to you at no charge. Sign in as a 1969 Mark III once you’re on our Website, go to the REFERENCE – TECH INFORMATION & PARTS DIAGRAMS section and Click on the Wiring Diagram.
Then you can move on to the switches and the other problems one at a time. It does seem from your description of the previous work that you will find much more to discover and repair.
Sincerely,
Bill