Dash light gremlins?

[Brownc62]

Hoping one thing is causing a myriad of electrical problems for me and hopefully someone has experienced this before. Currently working on a few big problems that I think are related. First, the brake light and the oil light in the dash come on as soon as I hook up a battery. They stay lit without the key in the ignition. I don’t see how or why they would be on without the key, but it caused my battery to die over night.  Now no other lights appear to be working, no dome light, headlight, taillight, or parking light.

Second, I can only get the engine to turn over if I jump the solenoid. It sometimes runs fine after that and sometimes stalls randomly as if someone turned the key off. When I try to turn the key to start it clicks one time and then nothing. I’ve replaced basically every ignition component including the under dash switch, battery cables, and starter cable. I’m wondering if there is some sort of grounding issue that all the problems have in common?

Yesterday I was able to briefly move the Eagle under its own power for the first time in 20 years and now I can’t keep it running...very frustrating  looking for some direction on how to start troubleshooting. Thanks!

[Mitch]

There is a ground on the firewall in the engine bay that may be causing some of your issues. It's between the brake booster and the rear of the engine. Make sure it is clean and grounded.

Also, look for ground points under the dash where the instrument panel is.

If you have a fully charged battery and one cable hooked up, touch the other cable to the other post. If you see lots of sparks you have a load or short somewhere. Remove the fuses one at a time and keep touching the cable until the sparks are mainly gone. That should help narrow down the circuit causing you trouble. (There will always be a little spark from the clock and/or stereo.)

[Taylor]

AMC did a very poor job on the electric systems in their vehicles, this includes the Jeep line, lots of connections that were wrapped in duct tape, etc. Still sorting out the mess that is mine. I keep finding more of that darn silver tape. I haven’t even started under the dash yet. The connection just behind the brake booster could have corrosion as well.

[mudkicker715]

I have seen this gremlin before. I was thinking about this since I first read the thread. My memory seems to recall that the diode trio in the alternator was to blame. I do not remember how to test that however and unfortunately.

Edited for maybe help......  🙃 maybe pull the alternator and have your local auto parts store test it.