Wiring problem

[1990pathy]

So I have a 90 pathy. And for the last few months it's been doing this weird thing where the volt meter will fluctuate from 12 to 15v or so and all the dash lights will freak out. the trans light brake light and the power at switch will start flashing in sequence with the voltmeter!!!! I have no our where to start. It doesn't effect how it drives it just freaks me out cause I don't want something to catch fire or melt. What could it be... Posted from my iPhone!!!!

[TahoeRunner]

I've heard that the alternator on its way out can cause the electronics to wig out before the alternator just quits charging. Especially if the voltage regulator in the alternator is failing it could be allowing surges and dips in the voltage coming out.

 

I'm sure others on here are more familiar with it, but I would have the alternator checked to start.

[NissanNismoZ]

Actually if i remember correctly that DOES mean a faulty alty.

Also, do you see your BRAKE light on too?

I remember someone saying if the BRAKE and A/T TEMP light comes on your alty is screwing up (too high or too low)

Just an idea that im sure someone will clear up shortly.

[1990pathy]

yes the alty is brand new...well a year old or so maybe i should go get it checked out thanks

[Mr.510]

That's a bad voltage regulator in the alternator. It's spiking the voltage and can fry all sorts of things from light bulbs and your stereo to the ECU, TCU, and just about everything else electronic in the truck. I would fix this ASAP before it damages something really expensive.

[1990pathy]

Ya I'm going to fix it tomorrow.thanks for the important info