Dash Lights Flickering

icanfixall

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Tonite I drove my rig and as parking it when I noticed the dash lights were flickering. I then saw the battery light flickering too telling me something is wrong with the charge circuit. My alternator has a new brush set in it from about 4 months ago. I have noticed this battery light flicker for maybe a year now. Can't find a reason for it either. Anyone have some ideas..
 

FoolhardyIDI

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You might have done this already. But I was having a similar issue. Turned out it was my Head light switch. The dimmer part to be precise.
 

The Warden

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Just a thought...a number of years back, I had a similar problem and noticed the ammeter wavering between zero and negative territory (slant-nose, so an ammeter instead of a voltmeter, and no battery light). I took a look at the alternator, and found that the plastic plug surround that held the small wires had disintegrated, and one of the small wires was loose on the connection, Pulled the one wire off, cleaned up the metal plug, crimped it slightly so it would grab the terminal on the alternator more securely, and been problem-free ever since ;Sweet

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It was one of the two terminals to the left of the main charge wire...I want to say it was the bottom one (field), but this was long enough ago that I don't remember for certain...
 

icanfixall

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Thanks guys but I'm not thinking my switch is at fault because of the flickering battery light. I will be looking at the alternator connections.
 

theguruat12

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I would say belt flopping, but you have a serp setup.... That's what it is on my 85 with v-belts, I have confirmed. Since your charge light is flickering as well, most suspicious of the light green/red stripe wire connections.
 

ironworker40

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You got all those gauges ,what does the volt meter read? Maybe voltage regulator is going bad and is right at the lower limit causing the light to flicker.
 

Agnem

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Those are harder to troubleshoot because you don't have access to the field coil directly. Replacing the alternator is the only real troubleshooting step to start with, aside from the normal checking of the wiring. I'd plug an analog voltmeter into your 12V accessory jack and watch it and see if the needle fluctuates also to rule out a lighting problem.
 
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