Headlight switch 94 Limited

[weaselonastick]

Hey folks... long time browser, first time with a question. I have a 94 limited with no headlights or highbeams. All other lights and signals fully functional. Replaced the multifunction switch with three different ones from a wrecker... no change. My prognosis is that the hedlight switch is toast. Here's the problem... the original headlight switch is obsolete... cannot find anywhere (Dealer and the web). The problem is that the Limited has an eletrocromatic rear view mirror which ties into the headlight switch. A current replacement switch does not work (wrong pin configuration). Need help!!! Either i need to get another switch (haven't found one at the wreckers), or modify the wiring to use the current replacement switch... I don't care if I loose the electrocromatic mirror. Original part number is SW2421 or F3TZ11654A. Thanks for any advice!

 

[Tbars4]

...go to the bottom of the forums page and contact kbabiak...

 

[budwich]

well... not to "poop on your prognosis" but how did you determine that your switch is bad????? With a meter, I hope... otherwise, you might just be chasing your "tail" with "parts and money". It sounds like you have "autolamps" (don't know for 94 options) and there are "other things" to check before "pointing" at the headlights switch.

 

[weaselonastick]

Budwich, I can't find a schematic for this particular switch, so I don't know the particular pin in/out configuration (to check with a voltmeter). I'm not an electrical wiz, so without the schematic, it would be a shotgun approach. I forgot to mention in my original post that my daytime running lights are working. I think I've checked everything else; bulbs, fuses, multifunction switch, etc etc.

 

[budwich]

well, in general switches aren't really that complicated. How many connections are there?

 

[weaselonastick]

From memory (I don't have the switch in front of me), there are approx. 6 pins on one connector, and 3 on the second connector. The second connector is for the electrocromatic mirror, so I'm not worried about those. I will check the first six to see if I can work it out. Is there anything else I can be checking besides this switch, but related to the autolamps?

 

[budwich]

IF you have autolamps, then the switch is used to power a relay which is used to turn on your lights.... and its actually not quite that simple (at least in 96...my drawings), there is two relays in "series", a "park lamp" relay, and a hmmm ... "head lamp" relay...

As for your unit... I suspect that only two are "input voltages" (hot all the time and hot in run), the rest are outputs from the switch.