Author Topic: No marker lights gauge illumination - light switch?  (Read 502 times)

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Offline colonel

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No marker lights gauge illumination - light switch?
« on: March 26, 2017, 01:09:06 AM »
1978 T/A

I had (and still have) problems with my high beams glowing dimmly while the low beams were on and ended up checking on the light switch after everything else I did to find the problem didnīt bring any improvement.

I took out the head light switch to see wether it was visually defective which wasnīt the case, so I re-installed it. From this moment on: no more gauge illumination and no more marker lights in the first step of the pull rod switch. The low beams come on in the 2nd step and the interior light comes on when the knob is completely turned to the left.

So, marker lights are the brown wires on pin #3 (or #7, actually I dont recall where I removed the wire) on the switch (to the lower left in my picture, the ones on the copper strip). Upon removal of the switch another time and measuring the switch pins with a multimeter while operating the pull rod in itīs various positions I found out that in "step 1" no connection is made between the +12V (red wire) pin and ANY other pin. In "step 2", connection is made to the #6 pin, right in the middle, bringing the low beams on. Picture attached.





To temporarily "fix" the marker light situation I took the brown wire from the switch connector, tapped into the red permanent +12V in the harness to the switch and installed an old simple pull switch I found in my tool box. It works. Now I have marker lights on the separate switch and low beams on the factory headlight switch in "step 2".

My thoughts were that the headlight switch must have failed due to age so I ordered a new one, just to find out that I still have no marker lights in "step 1". I also donīt have any gauge illumination. The new switch is basically the same than the old one, except thereīs a "B" cast in a place on the connector plate while it says "A" on the old switch. There are no pins in this area, though.

I also opened up and disassembled the old switch to understand how it works inside. Two slides make the connections while a cam humb in the rod presses down a pin for interior lights when the knob is turned. I re-assembled the switch and itīs back in the car now. Didnīt help my problem, though.

Can somebody please enlighten (haha) me if I may have dropped a wire while messing under the dash or why I cannot measure any connenction between the pins on the switch in "step 1"?
Thanks, Alex

Offline colonel

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Re: No marker lights gauge illumination - light switch?
« Reply #1 on: April 27, 2017, 12:38:05 PM »
Thanks for all the help that I got!

It was a blown fuse that I didnīt even know it existed.
Thanks, Alex