1985 Chevrolet Sprint



May, 28, 2009 AT 3:27 AM

Electrical problem
1985 Chevy Sprint Manual

My passenger side headlight is dimmer than the driver side. It is so dim I got a ticket for only having one headlight. I already replaced the headlight and it is still dim.
I went to the gas station and hed the mechanic adjust the headlight but that isn't the problem.

I unplugged the driver side head light and when I did it turned off the passenger side as well. So I than went and unplugged the (dim headlight) passenger side and it only turned off that side.

I had my roomate test the wires and they were ok.
I cant afford to take it to the shop So I must figure out what the problem is. If you can help me with any ideas on what could ne the problem, troubleshooting ect would be so appreciated. Thank you

2 Answers



July, 23, 2012 AT 6:35 AM

This very much sounds like a ground problem, These cars have power to the lights all the time and the switch uses the ground to make a complete circut. If you have a poor ground to that side, then your light is not going to very brite. It sounds like the passg. Side is trying to gets it's ground through the drv side, so what happens with your lights is most like exactly what you get with no ground on the pasg side.



July, 23, 2012 AT 7:04 AM

Open ground wire on the passenger side. Current is going through the low beam, can't find a ground path, so it continues on back through the high beam filament, over to the high beam connected together in the left side, then through the left bulb's ground. That's why the right one goes out when you unplug the left one.

If you don't know which wire is the ground on the right side, unplug the socket, then use a test light or voltmeter to see which wire has voltage when the low beams are turned on and which wire has voltage when the high beams are turned on. When those two are identified, the third one is the ground wire. Check that terminal in the socket for corrosion, then check if the wire is corroded off the terminal. If both are okay, check where that wire is bolted to the body to be sure it's clean and tight.

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