Hello. My name is Allen and I own a 1990 base Corvette. My problem is that the driver side headlight will go down but not up. I ran the wiring from the headlight motor across to the pigtail connector for the other headlight and it works both up and down! The pigtail connector has a green wire with black stripe and gray wire with black stripe. I noticed my gray wire with black stripe underneath the car had been damaged and repaired. Does this wire cause the motor to go up? I’m thinking perhaps the wire repair was not done successfully. Thank you for any input!y

 

Welcome to the forums Allen. I think you could be right, that repair might be your problem. If you think the wire is bad Redo the repair, then check it with an ohm meter. If needed, If the wire is good, the motor must be the issue. One wire raises the light and the other wire brings the light down.

 

Thank you for the welcome and for the advice Thomas. I’ll give it a try tomorrow and let you know if it worked out or not!

 

Well, unfortunately the gray wire with black stripe on it that looked damaged seemingly is not my issue. I made the wire repair and the driver side headlight continued to only go down when the lights are turned off but will not go up when the lights are turned on. This car has so many electrical issues I’m sure I will be back on this forum seeking advice and for now I will just keep trying to troubleshoot this headlight issue.

 

Welcome to the forum. Highly recommend that you get a factory service manual which will include wiring schematics for the car. I believe you can still get these through Helm, Inc. in addition to several aftermarket Corvette suppliers.

 

Allen I think you narrowed it down to an open circuit in the motor housing. Not sure if that is something you want to play with? Or replace the unit? Being a 1990 it's got some time on it.

 

Thanks 73shark, I’ve got a manual… reading it is the problem for me. Not my strong point but I will definitely give it a try. Thomas, I actually replaced this motor thinking that was the problem as well but I have the same issue. I will keep working on it and if I have any success or questions will let you all know. Thank you for the input!

 

I believe the way they control the direction of the motor is by reversing polarity on the winding. I suspect there are three wires going to the motor. One ground and two 12 volt lines. To change the direction of the motor, they just reverse the polarity on the windings. If this is the case then you can check it out by checking the voltage on the two 12 volt lines while switching the headlights on and off.

Before convicting the headlamp motor, you should verify that it's getting the proper 12 volt signals for up and down.

 

Allen, I can't believe you have two bad motors, you made sure the motor was grounded good, tried hooking the harness from the right side to the motor?

 

Allen you said the light goes down but when the lights are turned on does the motor run and not move or is it completely dead no noise in up mode at all?