1989 3.0 Discharging

[suntoy]

After a short running time my voltmeter shows the engine is discharging. I have replaced alternator, cleaned all terminals and checked wiring and can't find anything. Could it possibly be the gauge. Appreciate any info ya'll can give. Thanks

 

[chiefalen]

What wiring did you check? Anything on the back of the gauges?

 

[o2batsea]

With engine running put a multimeter across the battery terminals. Should see something between 13.2 and 14.4 volts. If it is 12 or below then you need a new alt. Always check with a multimeter, not some random gauge. Gauge is just a gauge, not a readout. It's no more accurate than a fuel gauge.

 

[suntoy]

I checked and cleaned the wire terminals at the alternator, assist module, intterrupter switches, cleaned battery terminals but haven't and don't know how to check voltmeter in dash. Sometimes wire gets hot going to starter.