reostat - headlight issue

Blake,

If there hasn't been any work done recently, and this started all of a sudden, I would suspect a bad headlight switch. I just went through a very similar situation with another owner's car.

When you turn the rheostat, does it also dim the headlights, or just the dash lights?

John

If I turn the reostat to the left, it dims the guage lights and the headlight doors close and I believe the lights also turn off.

Blake,

Some questions:

1. Has there been any work done recently under the dash or console?

2. What year is your car?

3. When you rotate the rheostat, does the headlight switch have to be on for the problem to occur?

4. If #3 is yes, is the headlight switch in the first position, second position, or does it happen in either position?

5. Does the ignition switch have to be on for the problem to occur?

John

Hi John,
I will be back with my car tomorrow. I shall do some testing and answer your questions. I contacted one of my Calgary Pantera buddies - he has an extra switch that I will install and see if the problem is solved.
Thnx, Blake

Hi Blake,

Before you change the switch, try this:

Verify that the electrical gremlins are still at work.

Under the dash, locate the molex type connector (large rectangular connector with about eight wires) for the hazard warning switch (not the turn signal switch).

Separate the two halves of this connector.

Test to see if the gremlins are still there.

John

Back with the car. First test - ignition off, light switch to first position(parking lights) - buzzing from switch. Light switch to second position - light doors do not open and increased buzzing level from switch. Must be the switch! If I turn reostat to the left, buzzing stops. Will replace switch and then post result. Thnx, Blake.

Something doesn't sound right with the headlamp door action tied to the instrument illumination rheostat. There must be something cross wired in there. I would get that right before replacing anything. Specifically check the switch wiring to this diagram:

http://www.panteraplace.com/El...0SWITCH%20WIRING.pdf

Here is the best wiring diagram reference site.
http://www.panteraplace.com/page107.htm

I just installed the headlight switch - no more buzzing, reostat works, headlight doors go up and headlights are on. One headlight is dim - I would imagine a faulty ground.
There are only 3 wires connected to the headlight switch. The ignition switch must be "on" for the headlight doors to open. The parking lights function without the ignition switch in the "on" position.
Any suggestions as to where to look for the headlight ground wire - driver's side.
Thank you, Blake.

Hi Blake,

Excellent!! From your report, it sounds like everything is working normally (except for the dim headlight).

Is the headlight dim on both high and low beam? I'm not sure where the ground wire is connected to ground, but it loops from the headlight to the parking/turn light to the side marker light and to the windshield wiper motor (most Panteras). The problem could be in the connector on the back of the headlight or the molex type connector near the headlight. You could tap into the black (ground) wire with a new wire and connect it (the new wire) to a new ground location.

Also check the fuse panel. Fuses 1 & 2 are high beams, and fuses 5 & 6 are low beams. Check for poor connections at the fuses and at the spade connectors.

Say hi to Doug M.

John

Blake,
That's what I did. Spliced into the ground wire at the headlights and ran a wire direct to ground. Both sides. You can get at this behind the front splash shields.

John B, Hi back. Was great to see you again in Phoenix. How did you know where the switch came from

Hi Doug,

Just a lucky guess. Actually, when Blake said that one of his Calgary Pantera buddies had an extra switch, I thought that it might be you.

Not to hijack this thread, but it was a pleasure seeing you again also. I'm glad that you didn't melt.

John

Thanks guys. I will check connectors, install new ground wires to both lights and check/clean fuse contacts.
Blake