Hello. I have an electrical short but not sure where it is coming from. All myguages aren't working. Alerts on my dash are on such as fuel even with a full tank and brake light is on even when brake is not. Radio light is on but radio doesn't work and neither do any of the buttons. My upper gauge for temp, dte, extra odometer...lights are on but guages don't work. Fuses are all ok. Does anyone know what this could be? Engine is also running just fine.
You've come to the right place! We can help you remove your shorts.
Seriously... You may have had a short at one time, but now you have an open. Shorts usually blow fuses (which causes an open) and melt wires. Opens usually just make things not work.
Any electrical trauma to the truck lately? Such as: got a jump start, gave a jump start, left lights on and ran down the battery but the truck just barely turned over and started, tried to tow a trailer and the trailer lights didn't work, snagged your toe on a wire bundle under the dash? Is there any aftermarket electrical equipment installed, like a stereo, DVD, alarm, remote starter, etc?
How did you test? With a test light, or just by looking at the fuses? Looking at the fuses can work, if you pull each one out of its socket and look at it with a strong light. If you're just looking at the fuses while installed, it's easy to miss a blown one. Also make sure you find _all_ the fuse boxes... sometimes there's one under the hood AND one in the dash. Your owner's manual will say for sure.
If you want to test with a test light, the best kind for this is the kind that looks like an ice pick with a wire coming out of it. First, pop the hood, put the alligator clip on the battery negative terminal, and poke the pick at the battery positive terminal. If the test light doesn't light up, the test light is bad. If it does light up, first check any fuses in the engine compartment. Most fuses that are 30 A and under will have a couple of metal spots on the face of the fuse. To test, you leave the alligator clip on the test light connected to ground (like the battery negative terminal, or a bare metal bolt that goes into the engine block or body), and poke the pick at each metal spot in turn. If both spots makes the test light light up, that fuse is good. If only one spot makes the test light light up, that fuse is bad. If neither spot makes the test light light up, that circuit doesn't have power at the moment and you can't draw any conclusions about that fuse. Usually you need to turn something on (ignition key, headlights, A/C) and try that fuse again.
If you do find a blown fuse, replace it with a fuse of the same current rating, and try again. If it doesn't blow right away, keep an eye on it. Every once in a while, a fuse blows because it's Tuesday, but there's usually a good reason. If it does blow again right away, you either need to chase the things that are powered from that fuse, or get assistance.
If you don't find any blown fuses, probably the next thing to look for is loose connectors. Start under the hood, then go under the dash... as much as you can reach by taking off the trim panels over your toes. Anyplace there is a wire connector, try to push the two halves together. If it moves and goes "click" when you do that, it was loose. If it moves but doesn't go "click", inspect it carefully... most connectors have plastic locking tabs and one of them may have broken off. If this has happened, sometimes a carefully-applied zip tie will keep the connector together.
Also, take a look at the individual wires immediately outside each connector. They probably disappear into a plastic tube or under electrical tape pretty quickly, but usually you can see a little of the wire. If you can see the wire, make sure it doesn't look burnt or charred. Sometimes a pin in a connector goes bad, which makes the connection heat up and melt the wire insulation. Follow the big bundles of wire around to make sure they aren't lying on anything hot or moving.
Don't freak out if you find some connectors with nothing plugged into them. Some of them are for test purposes and some of them are for options your truck doesn't have.
Good luck!
Matt Roberds
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