Wanted to check my mileage, turned the key on, then the dash lights to read it. When I pulled the headlight switch out, I got a strange 'buzzing' sound that changed as I rotated the rheostat (which feels rough) it alternated in sound, but never quit. The odometer was going crazy during all of this (little squiggles, flashing) It finally settled down and read correctly, but, as long as the dash lights were on, THAT SOUND was there! Turned the key off/on again after 20 minutes, (no engine start), hit the dash lights, and the noise was less, but the odometer was still crazed until it settled down and read correctly. Any clues? Should I throw some silicone on the headlight pull/push rod, or? :help:
What was voltage on the dash at this time? If steady and 12+ VDC I would check that all grounds were tight (far left side of raised part of dash.
If all that good, would probably replace the head light switch-- it could be arcing internally (there is a rheostat in it) which would drive electronics connected to it CRAZY.
Yup, 12+ VDC at the dash. I think it is arcing, (that's a good description of the sound) and it modulates as I turn the rheostat. Thanks, Brett! ^.^d
Trust me if it's only the rheostat is bad, and you dont feel the need to be able to dim the dash lights just jumper it. The Taiwan replacement switch is So bad I bought 2 both were so flimsy that the knob won't seat and hold. 20 hours of pure cussing frustration. Don't go there Mike if possible.
Explain 'jumper it', pleeze. I'm not even going to bother with fooling with it, since we hardly ever drive at nights and never use the rheostat, anyways, unless one of you 'wired wizzards' thinks it could be dangerous. Wonder if it can be cleaned? ^.^d
I removed my headlight sw. took it to car quest. They found it was a gm part, replaced it. Perfect fit lights dimmed perfectly.
Carquest S415P bought two of them, both were flimsy and would not hold enough alignment to retain the shaft. First one lasted for about a dozen uses, and then broke it trying to bend it into alignment, second one after about 4 hrs of tweaking is holding for now. Lucky Joe. Maybe Napa has a better built switch, but we no longer have a Napa in town, and very few hard core auto parts places left.
Headlight switch removal (http://www.foreforums.com/index.php?topic=31970.msg284751#msg284751)
My little issue is not over: just turned the ignition on to re-set the bad leveling jack (another thread :facepalm: ) and the odometer was still going crazy, even without the dash lights on! So it goes. :-\
Update went to move the coach tonight, gingerly pulled the trouble prone Carquest S415P light switch it came on. After moving the coach, I attempted to shut the headlights off and switch would not budge. DO NOT BUY the very flimsy Carquest/BWD S415P switch!!! I have $36 and about 20 hours of frustration invested in these POS. Tomorrow I will try an oem acdelco D6251D switch if I can find one. Will test flimsyness before leaving store. >:D
Common problem with the potentiometer. Clean it (the old headlight switch) by rotating and spraying Deoxit D5 into it, see if it clears it up. You can generally spray alongside the shaft, and check to see if there are any other openings in the body of the switch. Too much won't hurt anything, just clean the other contacts inside. This is a standard fix for older analog equipment.