sound coming from amp. gauge

[stevo5671]

I am getting a strange sound from the dash area on my Power Hawk...I think it is coming from the amp. gauge. It started a few days ago when I was driving at night. There was this sound almost like rocks being scratched against each other. I noticed the amp. gauge seemed to be making odd back in forth movements that seemed to coincide with the sound. It went away at idle and only made the noise when under power. When I went to shut off the headlight i noticed the switch was warm/slightly hot. I figured that was the cause and said I wouldn't drive at night till I switched out the switch. Well today...during daylight driving...the sound was still there. Any ideas?????

[jclary]

Just a few ideas...you could have a speedometer cable chattering due to a dry bushing or cable. The close proximity to the gauge could cause the gauge to bounce. However, if that were the case, your speedometer pointer should be dancing around too. Another cause could be arching and chattering points in a failing voltage regulator. One other source for a similar problem would be the coil and contact points in your clock if you have a stock clock. Just some possibilities to check out.

[N8N]

long shot, but is the dash well grounded? That would possibly cause the gauges to ground through the speedo cable, causing it to get hot, and also the amp gauge to fluctuate. Of course the idea that the cable just went bad on its own and vibration is causing the needle to move is probably more likely...

nate

[Jeff_H]

The headlight sw was hot correct? Did the amp gauge move back/forth the same w/o the lights on as with? Did the light flicker or blink while this was happening?

I suspect there is a intermittant short someplace. Is the circuit breaker for the lights on this car separate from the switch and is it wired between the ammeter and switch or is it after the switch ?

If the CB is after the switch and separate from it, then there could be a short between the switch and CB so that the CB does not trip but there are current surges to ground that cause the ammeter to move. The wires get hot and transfer to the switch if its close.

I think my first move would be to disconnect the power wire for the lights that comes off the ammeter and see what happens.

[Mike Sal]

If the speedo cable isnt' the source of the noise.....meaning it's actually from the power circuit.....it probably means the black smoke is trying to escape from your wires due to something. Time to start running things down. That headlight switch shouldn't get hot.
Mike Sal

[stevo5671]

Thanks for all the suggestions. It's not the speedo cable...that's what I thought it was the first time I heard it. Don't have a clock so it's not that and the voltage regulator is fairly new and too far away to be the culprit. It is coming from the dash area very close to the amp. gauge. I'm going to check all the wiring that goes to the headlight switch and replace the switch itself, and see where that leads me. I don't want to have to find out how good my insurance really is.

[stevo5671]

Found a loose wire on the headlight switch...seems to have fixed both problems.