Voltmeter dropped to zero
 

Got the fuel system all straightened out a couple of days ago. Last night I went out and started the truck, when I turned the headlights on I noticed the buzzer wouldn't shut off. Also the voltmeter has dropped to zero on the readout. My question is, is there a fusible link or individual fuse on an 89 R3500 with the 454 FI that controls this?

Re: Voltmeter dropped to zero
 

does it go back to normal when you turn off the headlights? this sounds like a ground issue to me, check the connections to your gauges and the ground for the main harness. should be by the parking brake pedal assembly

Re: Voltmeter dropped to zero
 

No, the gauge worked Sunday morning. But when I went back out Sunday night and turned the headlights on is when the "courtesy" buzzer stayed on and the voltage dropped off to nothing. I was kind of thinking ground, but the other gauges in the cluster are working. I assume they are all tied to the same ground? Either way, as long as a tornado doesnt blow through tonight, I will check that out.

Re: Voltmeter dropped to zero
 

Checked the grounds under the dash, everything looks fine. No broken wires or rusty connections in the interior. I think I will check the wire from the alternator to the gauge tomorrow.
I did check the alternator output while running, it was at 14.2-14.5 volts. So that is good. If it isnt a bad wire from the alternator to the gauge, I wonder if it is a bad voltage regulator?

Re: Voltmeter dropped to zero
 

Figured out the reason for why I wasnt getting a reading on the gauge. Blown fuse. No idea why the fuse blew, but I will work on that as I go. The whole electrical system in the truck is pretty hacked up from the PO, so it will be a work in progress for a while.