C3 window
Thread Starter
2nd Gear
Joined: Apr 2022
Posts: 2
Likes: 1
C3 window
C3 driver side Window will not go up or down. No indication the motor gets power. When I bypass the
ground to the motor it attempts to move the window. So 2 Problems? Where is the ground and where is it binding?
ground to the motor it attempts to move the window. So 2 Problems? Where is the ground and where is it binding?
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
What year?
How are you bypassing ground to the motor?
I can speak on the 70 design, don't know if it changed for later years.
Ground to the motor is through the chassis, no separate wire.
Two leads go to the motor, one for up, other is down.
Does the passenger side work?
If not I'd check the circuit breaker or power window tap on the fuse block.
There's a relay under the front of the console which may be checked as well.
If the passenger works, check for 12v on one of the two motor leads when pressing the switch.
Should get 12V on one side when pressing the switch, other side when pressing the opposite side of the switch.
No 12V would suggest a problem with wiring or maybe the switch.
Alternative would be to disconnect the wiring to the motor, apply 12V to one of the terminals, motor should go up or down depending on which terminal you tap.
If you get 12v but no movement, could be a motor issue or a jam.
Be careful when removing the motor, there's a spring which pushes the window upward, assists the motor.
How are you bypassing ground to the motor?
I can speak on the 70 design, don't know if it changed for later years.
Ground to the motor is through the chassis, no separate wire.
Two leads go to the motor, one for up, other is down.
Does the passenger side work?
If not I'd check the circuit breaker or power window tap on the fuse block.
There's a relay under the front of the console which may be checked as well.
If the passenger works, check for 12v on one of the two motor leads when pressing the switch.
Should get 12V on one side when pressing the switch, other side when pressing the opposite side of the switch.
No 12V would suggest a problem with wiring or maybe the switch.
Alternative would be to disconnect the wiring to the motor, apply 12V to one of the terminals, motor should go up or down depending on which terminal you tap.
If you get 12v but no movement, could be a motor issue or a jam.
Be careful when removing the motor, there's a spring which pushes the window upward, assists the motor.
Burning Brakes
Joined: Dec 2021
Posts: 805
Likes: 260
What year?
How are you bypassing ground to the motor?
I can speak on the 70 design, don't know if it changed for later years.
Ground to the motor is through the chassis, no separate wire.
Two leads go to the motor, one for up, other is down.
Does the passenger side work?
If not I'd check the circuit breaker or power window tap on the fuse block.
There's a relay under the front of the console which may be checked as well.
If the passenger works, check for 12v on one of the two motor leads when pressing the switch.
Should get 12V on one side when pressing the switch, other side when pressing the opposite side of the switch.
No 12V would suggest a problem with wiring or maybe the switch.
Alternative would be to disconnect the wiring to the motor, apply 12V to one of the terminals, motor should go up or down depending on which terminal you tap.
If you get 12v but no movement, could be a motor issue or a jam.
Be careful when removing the motor, there's a spring which pushes the window upward, assists the motor.
How are you bypassing ground to the motor?
I can speak on the 70 design, don't know if it changed for later years.
Ground to the motor is through the chassis, no separate wire.
Two leads go to the motor, one for up, other is down.
Does the passenger side work?
If not I'd check the circuit breaker or power window tap on the fuse block.
There's a relay under the front of the console which may be checked as well.
If the passenger works, check for 12v on one of the two motor leads when pressing the switch.
Should get 12V on one side when pressing the switch, other side when pressing the opposite side of the switch.
No 12V would suggest a problem with wiring or maybe the switch.
Alternative would be to disconnect the wiring to the motor, apply 12V to one of the terminals, motor should go up or down depending on which terminal you tap.
If you get 12v but no movement, could be a motor issue or a jam.
Be careful when removing the motor, there's a spring which pushes the window upward, assists the motor.
Safety Car
Joined: May 2001
Posts: 4,747
Likes: 1,642
From: Fairfax Virginia
Welcome to the Corvette Forum tjwdew!
I see that you joined us a while back but this is your first post! I hope that we can help you out in your work on a Corvette!
It is always good to have an idea about which year C3 you are talking about. I have an early 1968 and when I bought it the window was acting erratic. I cleaned the ground connection and the motor worked better, then I had to disassemble the window regulator to replace the ancient grease that was on it. A Hot Air gun makes removing the old caked on grease much easier. In this colder weather the old grease makes raising a window much more difficult as the grease gets even harder when cold.
The window switch would be a potential culprit, it is worth testing it. I have been using a material called DeOxIt and it is awesome at cleaning contacts and connections. It can take a old switch and make it work again just by cleaning the contacts with DeOxIt. I would also check your ground connection to your door with the window issue. A weak ground connection caused by a dirty wire can really make problems. Everything works better when it is getting Full Power.
When you have a moment open your "Profile" and tells us a little about your Corvette. Knowing the year and model helps us help you. The more we know the better it helps you! Any accessories or modifications are usually important!
I see that you joined us a while back but this is your first post! I hope that we can help you out in your work on a Corvette!
It is always good to have an idea about which year C3 you are talking about. I have an early 1968 and when I bought it the window was acting erratic. I cleaned the ground connection and the motor worked better, then I had to disassemble the window regulator to replace the ancient grease that was on it. A Hot Air gun makes removing the old caked on grease much easier. In this colder weather the old grease makes raising a window much more difficult as the grease gets even harder when cold.
The window switch would be a potential culprit, it is worth testing it. I have been using a material called DeOxIt and it is awesome at cleaning contacts and connections. It can take a old switch and make it work again just by cleaning the contacts with DeOxIt. I would also check your ground connection to your door with the window issue. A weak ground connection caused by a dirty wire can really make problems. Everything works better when it is getting Full Power.
When you have a moment open your "Profile" and tells us a little about your Corvette. Knowing the year and model helps us help you. The more we know the better it helps you! Any accessories or modifications are usually important!
Thread Starter
2nd Gear
Joined: Apr 2022
Posts: 2
Likes: 1
What year?
How are you bypassing ground to the motor?
I can speak on the 70 design, don't know if it changed for later years.
Ground to the motor is through the chassis, no separate wire.
Two leads go to the motor, one for up, other is down.
Does the passenger side work?
If not I'd check the circuit breaker or power window tap on the fuse block.
There's a relay under the front of the console which may be checked as well.
If the passenger works, check for 12v on one of the two motor leads when pressing the switch.
Should get 12V on one side when pressing the switch, other side when pressing the opposite side of the switch.
No 12V would suggest a problem with wiring or maybe the switch.
Alternative would be to disconnect the wiring to the motor, apply 12V to one of the terminals, motor should go up or down depending on which terminal you tap.
If you get 12v but no movement, could be a motor issue or a jam.
Be careful when removing the motor, there's a spring which pushes the window upward, assists the motor.
How are you bypassing ground to the motor?
I can speak on the 70 design, don't know if it changed for later years.
Ground to the motor is through the chassis, no separate wire.
Two leads go to the motor, one for up, other is down.
Does the passenger side work?
If not I'd check the circuit breaker or power window tap on the fuse block.
There's a relay under the front of the console which may be checked as well.
If the passenger works, check for 12v on one of the two motor leads when pressing the switch.
Should get 12V on one side when pressing the switch, other side when pressing the opposite side of the switch.
No 12V would suggest a problem with wiring or maybe the switch.
Alternative would be to disconnect the wiring to the motor, apply 12V to one of the terminals, motor should go up or down depending on which terminal you tap.
If you get 12v but no movement, could be a motor issue or a jam.
Be careful when removing the motor, there's a spring which pushes the window upward, assists the motor.
Thanks for your comments. The ground connection I used was a wire clip to bare metal under the center console
and to the motor itself. So the motor is good. At that time, their was no place on the door that I could find a good ground.
With some adjustment I now have a good ground connection on the door.
Both windows now work.
