Something's haywire

Driving to work the other day I noticed the alt. gage was really high towards the 'c' and a few miles later smoke started coming from behind the dash in the area of the gage. I pulled over and tried to shut the truck off, but it kept on running with the key out! I got back in and drove towards a gas station nearby, but the gage then went back to normal and the truck was fine for a few days. I looked over the wiring and didn't notice any shorts or blown fuses, so I pulled the radio I installed out to rule out the possibility I made a mistake or messed something up installing it. Tonight it did the same thing again, but no smoke. I noticed that the heater fan cuts in and out when it is acting up as well. I had to pop the hood and pull a wire to turn the truck off! Anybody know what might be going on?

YIKES !!!! make sure your insurance is paid. and i am not trying to be funny. i also would not park this unit anywhere near any thing you want to keep and definitely not in your garage! sorry i tend to think like a firefighter. I have very little experience with these units and what i have had was not real pleasant. Bob H ?

Dave P said:

YIKES !!!! make sure your insurance is paid. and i am not trying to be funny. i also would not park this unit anywhere near any thing you want to keep and definitely not in your garage! sorry i tend to think like a firefighter. I have very little experience with these units and what i have had was not real pleasant. Bob H ?

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If that is the case, then driving towards a gas station would'nt be great either!

i was thinking that also, but did'nt want to sound like any ones mother.

Most of the electrical load on this goes through the amp Gage in the dash. It is not uncommon for the connection to the Gage in the dash to fail and take out the instrument cluster and the amp Gage. I had this happen in my 77 snow commander w150. This is pretty much the same as you truck. I am not sure how it could have failed and energized the circuit to the distributer but I would pull apart you dash and check he amp Gage and instrument cluster for short or other damage before it causes a fire.

Chryslers are bad about that-the main feed goes through the ammeter, so if the system grounds out, it tries to pull too much amperage through the ammeter and it burns up, thus killing the entire electrical feed for the vehicle. Also, the insulators on the back of the gauge dry up and fail.

This however, sounds like some other isse, like the alternator trying to overcharge.

You can bypass the Amp gauge by taking the large red and black wires off it and connecting them together. Yes, you can do that, even though one is red and one is black. The charging system will then act normally but the gauge will be dead. In my experience, it sounds like you have either a bad voltage regulator, or the wiring to the ignition switch has melted together. Check under the dash, right around the steering column. There will be two wide, flat, sets of wires that have fairly large connectors. One is frequently blue and the other white. The one to the ignition has the larger gauge wires in it. With age, and stress on the ignition components, the connector will overheat and melt causing shorts and other issues. The connector will be discolored and obviously burnt if this is your problem. If it is bad, just bypass it and wire and solder everything direct. This will make it a pain to swap out the ignition switch in the future, but will eliminate the problem. The voltage regulator is an easy and cheap swap. If that doesn't fix it, keep the extra regulator as a spare. I normally carry a spare voltage regulator, ignition ECU, and coil resistor. Get the genuine Mopar stuff, it is truly worth the extra cost. At the very least go with NAPA parts if you absolutely have to save money. The electrical parts from Advance, AutoZone and similar chain stores are not worth the price and time to go get them. Just my .02

One other thought, check the fuse box in the glove compartment. They are also famous for overheating and causing problems. Especially when the heater fan is acting weird. Again, obvious melting of the components will show you the problem. Best thing I have found to fix that is to swap to the later style fuse box with blade fuses. It's a wiring pain to swap and get it to fit in the space of the old one, but it works and has never given me problems other then getting the wipers to turn off when the ignition is turned off, lol...

I didn't find anything wrong with the ignition wires or connectors. The alt. gage wires were almost fused together and the insulators were melting. i connected these together and the truck seems to run fine although I know I really didn't change anything and its still probly pumping too much juice. So if I change the voltage regulator that should be okay?

Thanks for the great advice guys, it saved me lots of trouble.

P.S. I thought about driving to a gas station as a possible fire hazard, but it was a big station and I planned on parking around back. You know... by the propane tanks...

I'd have the Alternator checked just to be sure. Normally you can get away with replacing the regulator, but just to be sure I'd test the alt also. I've had a few do the over charging thing even as far as to blow the vent caps off the battery. 140 amp alternator was charging wide open at 215 amps, lol...