77dreamcometrue

Hey guys I'm new here so please don't beat me up to bad... Just got my first C4 corvette and of course I have a headlight issue, only my issue I can not find on the forum. My passenger headlight motor does not run at all any ideas on how to diagnose the problem? Thanks in advance!

don hall

Welcome....... What year is your vette? Probably doesn't make much difference, as most C4s have the same headlights (?).
I'm assuming the problem is the lamp housing does not rotate when the light switch is activated.....correct?

If you are familiar with a meter, you can determine if 12 volts is applied to the motor when the switch is turned 'on'.
If 12 volts is available at the motor, and the motor doesn't react, the motor may need replacing.

This link will provide you with approximate replacement costs for the components. It is not
a recommendation for purchase....you can do your own price search once it is determined that
the motor is faulty: http://www.zip-corvette.com/84-96-c4...rs-relays.html

77dreamcometrue

1994 for what it's worth, you are correct I tried having someone switch the light on and I listened nothing coming from that motor.

77dreamcometrue

Just for my info if there is no power what would be the next logical stop?

don hall

If no power (voltage) at the motor, you will need to trace the current from the switch to the motor using a meter.

Read the text at the bottom of the link I posted, it
provides rebuild details, rather than replacement.

If you are not savvy using a meter, it may be best to have an auto-electric tech diagnose your system.
The tech may determine the problem, and instruct you how to correct the problem.

aklim

If you plan to keep the car, I suggest buying a scanner, not code reader and an Factory Shop Manual. Scanner can wait since it isn't needed for this job but it will come into play later.

scrappy76

I assume you have popped to hood and checked connections, wiggled the wire. Also make sure you actually put your ear to the motor when trying to get it to work, could be the gear is completely stripped and the motor still working just very quiet. I know this sounds a little far fetched, but I am an optimist.

pcolt94

There are 2 headlight fuses in fuse block 2 under the hood. Fuses 3 & 4 are 30 amp fuses and one is for each headlight motor.

Another thing you might try first is manually unscrew the headlight up about 1/2 way. Then turn the headlight switch on, then off and see if it will lower by itself. If it moves, the motor is OK.

I would try to reseat all the plug connections. At the headlight and the controller which is located on the left side by the vacuum ball and air injection motor. It's square and has a couple of plugs on it.

Before you do the plugs on the controller, remove the negative battery terminal first to remove power to the car. It's not to protect you, it's to prevent a voltage spike to the controller.

77dreamcometrue

Thanks everyone for the quick response I will work on this today and let everyone know how it turns out.

Mishawaka

Check for voltage and ground at the motor and work your back.

pcolt94

There is no ground on the motor. The controller reverses voltage polarity to drive the motor and the headlight up or down.