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Mysterious Electrical Problem

I have been struggling with this problem on and off over the past couple months and it has me stumped. The basic problem is that I lose all electrical functionality - no lights, no radio (presets reset), no auto door locks, no start. I had the battery tested at the local shop and it tested out just fine. This generally happens after I have driven the car, so it isn’t like the battery is draining out overnight while sitting in the garage.



Today, I got in, and it started fine. I drove about 2 miles and was parking. I’m in snowy Michigan so on street parking usually involves plowing through slushy crap built up on the side of the road. I was being lazy and accidentally let out the clutch after I finished parking stalling out the car. I went to start back up the car and nothing. No clicking, no indicators that the car had power what so ever. If I hold the key in the run position for a few seconds, the temp gauge and gas gauge will slowly rise up from their resting positions. I left the car for about 15 minutes, before I got back in. The first time I tried it, still nothing. Tried in again a few seconds later and it started right up. Once started, it is like the battery had died because all of the radio presets are reset. It ran fine after that. I got home and it worked fine later that day as well.



I have checked the battery for a loose connection on the battery and also for a loose ground wire, however, beyond that I don’t know what else to look at. Someone mentioned to me that it could be a short, but no idea where.



Any one have any idea???

Most people first say…“I have a Make, Model, and Year…”

Tester

Whoops! I got so wrapped up with the details, I forgot about the requirements…

The car in question is a 1995 Plymouth Neon (red if that matters).

OK! That makes a big difference!

Have the wiring harness that runs behind the engine checked to make sure the clips haven’t broken, and now the harness is against the engine and melting.

Tester

The first thing I would do is disconnect the battery and clean the connections.

I cleaned the battery connections this weekend and I’ll watch it the next week or two to see if I have any more problems. Unfortunately it comes and goes so it is just a matter of time to figure out if that helped.

Tester - if it is the harness melting, wouldn’t that melt and then stop working completely? I have made multiple 100+ mile trips since the initial problems so I would think that I would have completely melted the harness by now if that was the problem. Does that make sense or am I overlooking something?

The problem is due to a bad connection (not a short) in the power lead between the battery and the fuse panel under the hood. Hopefully it was just the battery connections you cleaned. The problem could also be due to a flakey fusible link near the battery. There should be a wire leading from the battery or the starter that ties to the main fuse panel under the hood. By using a test light probe and watching the light while the probe is connected to the main power buss lead in the panel you may be able to find the trouble by moving and tapping on suspected trouble areas.

Thanks to everyone for the suggestions. I cleaned the battery terminals about 2 weeks ago following the tips at http://www.howtocleanstuff.net/auto/mechanical/how-to-clean-car-battery-terminals/. So far, I haven’t had any problems, so I am calling it a success!

Great! You cleaned the battery cable terminals, and battery terminals (posts?), and ALL WAS WELL. To keep the corrosion from coming back, take the battery cables off the battery, smear a healthy amount of petrolatum (or, dielectric grease) on the posts and terminals. Reattach.