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Lights problem

1975 dodge sportsman.

So today I got last part needed and my rv runs almost like a dream still needs few minor tuning with carb now but I go to check lights to see if I need to replace any of them and during the time the engine starts to bog as if it was about to die so I got to give it some gas as it was still warming up and my lights blew. Head lights turn signals and even the dash lights that show ur turning that u have brake on the whole set up basically I think I’m missing a ground wire I checked the ones I see and they look fine and I found a ground wire under the hood not bolted to anything it was tucked away anyone have any ideas?

Slightly confused but my thought you will not blow a fuse because of a bad ground connection.

can you please use terminology that we understand . . . ?

What do you mean “blew” . . .

Sealed beams shattered . . . ?

Fuse blown . . . ?

The wiring for the lighting is smoking . . . ?

Have you verified that the aforementioned lights have power?

If they have power, have you verified ground?


Check the fuses affecting the lighting system first. Usually each light fixture (or all the fixtures in one part of the vehicle) has it’s own separate ground wire from the fixture to the chassis, so it seems unlikely this would be a grounding problem. This assumes the engine still runs, radio works, etc. If it isn’t the fuse there’s a possibility-- though unlikely – that rev’ing the engine caused the alternator voltage to spike, and that damaged the lights or their fuses. If so, that’s an alternator or battery problem. Make sure the connections to the battery are not corroded as part of the battery’s job is to help the alternator control it’s output voltage. There should some be fairly thick grounding wires from he engine and stuff attached to the engine connected to the chassis here and there. Do you see them? Check the connection from the battery negative post to the chassis too, that it’s not corroded where it attaches to the chassis. I doubt that’s the problem but good idea to do for getting a 1970’s vehicle back on the road.

It sounds like a voltage regulation problem. When you revved the engine, voltage spiked and blew everything out. Your vehicle has an external voltage regulator, which may be the problem. It looks like this:

You don’t have a 24 volt battery. Run away from “the guy” who told you this.

Its was a auto zone guy lol and yeah I replaced that regulator for I new one is it possible it’s the battery it self

Trust auto zone to read code’s only do not rely on them for mechanical advice.

Not the battery. It cannot put out more than its rated voltage. There may be more than one battery size listed for your truck, but they are all 12 volt batteries. More likely a bad or missing ground connection. For example, the case of the voltage regulator must be properly grounded for it to work properly.

That’s what I was thinking so is it possible the ground wire I found tucked away the used to ground the voltage regulator or something else that’s not grounded also found out my fuel guage and battery guage and oil guage and alternator guage gos up when I rev the engine. Also idk if this help but the voltage regulator is mounted to the body of the rv its metal is touching the metal of the rv. I been trying to find a wiring diagram that might tell me where all that grounds are and if any are missing but cant find a book on the rv only one for a van