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I have a 1988 Corvette with only 55k on the clock. The issue that I am having is that the passenger side headlight with not rotate. The light will come on, but there is not rotation from the motor. So, how can I tell if the bushing are bad? Or could this be another issue?
most likely the bushings. father time is no friend to plastic bushings, they will just disintegrate at will. if they haven't been replaced before, 26 years is a long time for them to last. they are a pita to replace but do able. there are videos on line that will guide you through the process. I did my 89's about 15 years ago and going to replace the 94's as soon as I get off my butt and order the rebuild kits.
There is a black plastic **** atop the HL motor that allows manual operation of the HL motor.
-Grasp the motor on the good HL motor and rotate it rapidly to get a feel for reaction of the HL assembly.
-Then do the same for the faulty HL.
If the faulty HL does not move the problelm is most likely the bushings.
There are several things that can cause this. Motor,wireing,headlight module,gears, agree if you can turn it up by doing it manualy it most likely is not the gears. The next step would be to test to see if the motor operates if you suply the nessary voltage and ground. If the motor operates doing this test to see if you are getting the nesseary voltage and ground to the motor if this checks out it is most likely the head light module.
Ok, so I took the motor apart to find that the bushing were toast. Replaced the bushing and gear, put everything back together, and it still doesn't work. I can manually open the light. But, it will not rotate on its own. I unplugged it and put a tester on the plug coming from the car and the I was getting power. So, could the motor be gone?
Disconnect the two pin plug going to the motor. Use an ohm meter and measure the resistance of the motor windings. Should be 1 ohm of resistance. If not you could have damaged one of the brushes.
You can also apply 12 volts direct from the battery to the motor plug and verify the motor runs.
Disconnect the motor and check the connector for 12v, if no 12v check the inputs to the module and the outputs from it.. With the switch off you should get 12v, with it on you should get reversed polarity..
Disconnect the two pin plug going to the motor. Use an ohm meter and measure the resistance of the motor windings. Should be 1 ohm of resistance. If not you could have damaged one of the brushes.
You can also apply 12 volts direct from the battery to the motor plug and verify the motor runs.
There is no relay, rather a Headlight Control Unit (HCU). The HCU is located in the lower LH front of the engine compartment.
The wiring is:
C1 Pin A - Gry/Blk to LH HL motor assy
C1 Pin B - Grn/Blk to LH HL motor assy
C1 Pin D - Gry to RH HL motor assy
C1 Pin C - Dk Grn to RH HL motor assy
C2 Pin A - Yel to Lt Sw pin J (on trigger)
C2 Pin B - Red to Fusible Link G
C2 Pin C - Wht to Lt Sw pin G (off trigger)
C2 Pin D - Blk to Gnd
C2 Pin E - Red to Fusible Ling F
First I would unplug the headlights from the HLC. To test the RH HL motor jumper the Dk Grn wire to Gnd and touch a +12Vdc jumper to the Gry wire. This should cause the RH HL to open. Do NOT hold the +12Vdc to the Gry wire after the HL is fully open.
Repeat the test on the LH HL motor using Dk Grn/Blk & Gry/Blk wires.
If both HL motors report back for the next test sequence involving the HLC.
The headlight motors use fusible links for their main power.. The easiest way to check them is to check for 12v at the control module..
Location of fusible links..
There is nothing between the module and the motors but wires.. Did you ohm check the motors, or put 12v and ground to the motors?? Did you check power out of the module with key on and key off??
Headlight issues
