"How To Find The Wiring Problem on 1995 Chevrolet Silverado"

Red 1995 Chevrolet Silverado 1.5L Left Side View

I own an 1995 Chevrolet Silverado TBI Z71 with a 5.7L engine. The alternator is new and even had it checked at 2 different parts stores. It’s good. Here’s the problem though, it isn’t charging. It’ll show the alternator light (which is a picture of a battery) and when you give it some gas, it goes away. Well, the battery charge on the gauge still goes down and then the truck will die because the battery itself goes dead. As it got dark outside we noticed that the high beam lights (only the high beam) lights were orange when it was running and the lights were off. We put the lights on and even being on a charger it would still kill the truck as soon as you turned them on. We tested the battery and the battery is still good too.
Well, the lights only glow orange when the truck is running. When the key is in the ‘on’ position they don’t glow. Cranked the truck and pulled the lighting fuse and the orange glow is STILL there but the head lights won’t come on. We checked the ground from the battery to the fender and it’s hooked and tight and the same goes for the ground from the headlight harness. The ground is good. Anyone have an easy way for me to find the problem or to at least narrow it down? Any help will be appreciated. Thank you.

Answer: Sounds like the charging circuit is somehow connected to your highbeams? Has anyone micky moused with the wiring? If not, look closely under the hood for melted wires. You’ll have to get a haynes or chiltons manual with a wiring diagram and a handheld voltmeter. If you’re not into electrical troubleshooting, find a mechanic that isn’t scared of it. The first thing to check is the charging circuit. Measure the voltage at the battery key off, key on engine off, key on engine on. The first should be about 12.5 volts,(might be lower because your battery is weak) the second should drop a tiny bit around 12.2 volts, and engine running (alternator running) about 13.8 volts. I’m guessing the last measurement will be off. The large orange wire on the back of the alternator should be directly connected to the + post on the battery. If not, there’s a fusible link in the wire that’s open.