1999 Pontiac Firebird All 4 headlights on in low-beam mode

1999 PONTIAC FIREBIRD
107,000 MILES • 6 CYL • 2WD • MANUAL
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BIGFOOTBUILT
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When my lights are set to low-beam, all 4 headlights come on. Both left side lights are very dim, and the right side right headlight is bright. The left-front parking light is out when in low-beam, but both fog lights work properly.

When my lights are set to high-beam, only the right side headlights come on. Both fog lights go out, but both parking lights are now working.

I have changed my left-side headlamp actuator motor twice due to the gears stripping out. I have double-checked the wiring harness for the actuator and it can only go on one way, since it is idiot-proof. The inside of the harness looks in good shape, and I have tried the old wiring harness just to see if that was the culprit, but it doesn't appear to be the problem. I checked this because I didn't see this problem until a couple of weeks after I replaced the headlamp motor assembly. I also checked the high-beam switch under the steering column. This switch actuates a metal rod that runs down along the steering column to some other switch just above the pedals. I didn't see anything unusual there. What else can it be? Thanks in advance.
Jun 20, 2008 at 2:08 PM
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MASTERTECHTIM
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sounds like you are missing the gropund for the head lights. check both head light ground wires and fix the bad ones and then get back to me if that is not the problem. when the lights are dim this means its backfeeding through the other circuit looking for a ground, thats why they are all on and some are dim
Jun 20, 2008 at 8:49 PM