When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Only put a few miles on this car before I tore into it, headlight motors weren't working for whatever reason. Fast forward several years to 6 months ago and I had them on the bench and th.ey worked both directions, both motors. I still tore the gear drives apart, cleaned, lubed, and reassembled. Bench tested them again, no issues. After reassembling the buckets, setting stops, and setting the stop switches, I tested the motors in the car.....all worked. This was with a remote battery and jumper wire. Installed the wiring a few days back, hooked up power, no worky. Headlights come on, rollover switch does nothing. Okay, trace the power, switch has power. Unplugged the terminals to motors, they both have power on each leg up and down per switch mode. All's good. Check continuity for grounds, all good. Take the motors out, bench test again, all good. Both motors work in each direction. WTH! Now, I switched over to continuity, and for whatever reason, I checked between the ground and each lead....I have continuity between each spade to the housing and continuity blade to blade on both motors. I'm no electrician, but that shouldn't be ... correct? I'm lost here.
If all connections and power logic check out, make sure the ground screw is not protruding too far into the motor housing which can cause the armature to jam.
Measure resistance from the mounting bracket bolts on the motor bodies to a known good chassis ground. Or try a temporary jumper wire from the mounting bracket bolts on the motors to battery negative.
I have continuity between each spade to the housing and continuity blade to blade on both motors. I'm no electrician, but that shouldn't be ... correct? I'm lost here.
That’s normal with most multimeters set to beep for continuity, it’s resistant, which is normal because one brush is soldered directly to the housing, so that makes sense.
The ground screw (if original) isn’t long enough to interfere with the armature, but check it anyway.
With the motors unplugged, are you getting power to both sockets on the plug, up & down ?
Yes, power to both. I just went around again and tested directly with a battery, bypassing the car's circuitry. Works fine in the car. Holding the aligator clip in my fingers, it was warm, so I'm assuming the motors are tripping the 30 amp breaker? I don't have a multimeter that reads more than 200ma so I'll have to borrow one and check the load. I'm just assuming it's tripping that 30a breaker.
If the voltages read as you say, it sounds like your motor grounds aren't connected back to the ground on the car. Hook a jumper on the bumper bracket or any good ground and connect it to the motor housing and see what happens. The only other thought would be if both were mechanically binding. When you push or pull the rollover switch, does the battery gauge on the car flicker to the left? If it doesn't, I think you are missing grounds on the motor cases.
Last edited by 65GGvert; Mar 17, 2025 at 09:07 PM.
I just read your original post again and it would seem from your tests that the switch, wiring to the switch, the circuit breaker, or possibly the bulkhead connections could be the problem.
I think you’re going to have to work backwards from the firewall, (if it works from there) back to the switch with jumper cables and alligator clips etc. to trace it.
Sounds like the motors are ok from what you described.
Good luck.
Just triggered the rollover from the cabin, amp gauge barely moved if at all. It drops several amps when I flick the lights on though. I do have a bulkhead issue, the upper tabs clipped, but I couldn't get the lower ones to clip over the tang, probably a bit of fatmat under the fuseblock. I put that off for another day. Again, I get full voltage to the terminals. I know DC can be finicky without the best of connections, so if you'all feel the motors are fine, I'll address that issue before I borrow a multi-meter and test the motor load.
I just read your original post again and it would seem from your tests that the switch, wiring to the switch, the circuit breaker, or possibly the bulkhead connections could be the problem.
I think you’re going to have to work backwards from the firewall, (if it works from there) back to the switch with jumper cables and alligator clips etc. to trace it.
Sounds like the motors are ok from what you described.
Good luck.
problem is, he said he got voltages on both left and right motor plugs for both the up and down position of the rollover switch. if that turns out to be correct, it only leaves the ground or both motors doing the same thing.
problem is, he said he got voltages on both left and right motor plugs for both the up and down position of the rollover switch. if that turns out to be correct, it only leaves the ground or both motors doing the same thing.
Yes maybe, so attach the power supply ground to the block or the core support and just run (+) to the motors and see what happens.
Went around the system, bypassing the breaker, thinking it may just trip everytime I hit the load......nope. Then I pulled the switch and stuck a hotwire between the hot and each lead....bingo! It was the switch. The original switch tested out fine with continuity, but wouldn't hold the current load. That's why the amp gauge just twitched a bit, but didn't move. I tore into the switch, cleaned, sanded the points, dielectric grease, and installed....bingo again. All's good. I priced the repop switch and for $140 and probably offshore garbage, I decided to spend a bit of quality time with this one. Thanx for everyone's thoughts.
I priced the repop switch and for $140 and probably offshore garbage, I decided to spend a bit of quality time with this one. Thanx for everyone's thoughts.
They are salvageable, if the contacts inside are not too burned or corroded.
Worth trying anyway
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.
Crazy headlight motor issue
