Strange electrical charging circuit problem
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Elder User
Joined: Jul 2001
Posts: 510
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From: Portland, OR
Strange electrical charging circuit problem
Hello & here's what happened:
Wife comes home from work & van (93 AWD, 105K) is driving fine. Tries to leave an hour later, nothing works, not even dim lights. I try batty with a test light, looks weak. I hook up to charger & 10 minutes later it fires right up, then charge an addt'l 30 minutes. Driving around, I notice that volvtmeter is way down at idle speeds, looks normal at higher RPM. Does this sound like a bad alternator? This happened two days ago and now the voltmeter position looks more stable & normal.
I can't understand why (when it was dead) that I didn't even get ingition lights to turn on when it wouldn't start. Does the electrical solenoid near the battery control all power except what goes directly to the starter? One of the terminals on it looks pretty rusty, could that be a problem also?
Thanks,
Mark
Wife comes home from work & van (93 AWD, 105K) is driving fine. Tries to leave an hour later, nothing works, not even dim lights. I try batty with a test light, looks weak. I hook up to charger & 10 minutes later it fires right up, then charge an addt'l 30 minutes. Driving around, I notice that volvtmeter is way down at idle speeds, looks normal at higher RPM. Does this sound like a bad alternator? This happened two days ago and now the voltmeter position looks more stable & normal.
I can't understand why (when it was dead) that I didn't even get ingition lights to turn on when it wouldn't start. Does the electrical solenoid near the battery control all power except what goes directly to the starter? One of the terminals on it looks pretty rusty, could that be a problem also?
Thanks,
Mark
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Joined: Apr 2001
Posts: 3,818
Likes: 3
Strange electrical charging circuit problem
At first glance, it would seem to the alternator going bad. Did your wife happen to be using the rear A/C or heater frequently just prior to the dead battery?
The reason I ask, is I have a similar problem with an '91 AWD. Running the rear unit seems to put a huge draw on the alternator reflected by the dash volt gauge, but only at idle. (Van is 100% original, no aftermarket items). The other oddity with the rear unit is with the driver controlled switch for the rear unit. Under A/C, the blower will shut itself down when the ignition key is turned off, but on heat or vent will continue to run, if the driver controlled switch is left in an active position, until the battery is dead. I'v always suspected a correlation between big amp draw and this switch but so far I can find no explanation and everything works fine as long as the vehicle is not left on prolonged idle with the rear blower on.
About six weeks ago, I had the same mysterious dead battery experience as you describe. Took it for a system check and both alternator and battery were declared good. After short recharge and start, no problems since then. Sorry, don't have more useful information for you.
I'd be curious to know if you find anything more definitive with your van.
The reason I ask, is I have a similar problem with an '91 AWD. Running the rear unit seems to put a huge draw on the alternator reflected by the dash volt gauge, but only at idle. (Van is 100% original, no aftermarket items). The other oddity with the rear unit is with the driver controlled switch for the rear unit. Under A/C, the blower will shut itself down when the ignition key is turned off, but on heat or vent will continue to run, if the driver controlled switch is left in an active position, until the battery is dead. I'v always suspected a correlation between big amp draw and this switch but so far I can find no explanation and everything works fine as long as the vehicle is not left on prolonged idle with the rear blower on.
About six weeks ago, I had the same mysterious dead battery experience as you describe. Took it for a system check and both alternator and battery were declared good. After short recharge and start, no problems since then. Sorry, don't have more useful information for you.
I'd be curious to know if you find anything more definitive with your van.
Thread Starter
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Elder User
Joined: Jul 2001
Posts: 510
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From: Portland, OR
Strange electrical charging circuit problem
Boy, did I ever find something and, while it was a cheap fix, it sure was strange. At the main switch, just to the right of the battery where the main feed circuit goes to (not the starter), I was looking at the battery side of it and noticing a fair amount of corrosion, jiggled the wires and the lead from the battery circuit fell off! The terminal had cracked in half, between the end of the crimp and the ring. There was virtually no "shiny metal" so it had be cracking/corroding over a period of time. I'm convinced of several things:
1. The other day, when the battery looked dead, this circuit was basically broken but somehow reconnected itself again.
2. The terminal itself is made from very thin stock, not strong enough.
3. The nuts on mine were steel, should have been brass like the stud appears to be. I think this would have prevented the corrosion.
Crimping on a new terminal fixed everything and I put on brass nuts (interesting not metric but 5/16 UNC). Whew! I got lucky as I found it just by "sniffing around" while it was in the driveway. I can't imagine what would have happended if the circuit had opened while driving. I think the van would have come to a screeching halt.
Mark
1. The other day, when the battery looked dead, this circuit was basically broken but somehow reconnected itself again.
2. The terminal itself is made from very thin stock, not strong enough.
3. The nuts on mine were steel, should have been brass like the stud appears to be. I think this would have prevented the corrosion.
Crimping on a new terminal fixed everything and I put on brass nuts (interesting not metric but 5/16 UNC). Whew! I got lucky as I found it just by "sniffing around" while it was in the driveway. I can't imagine what would have happended if the circuit had opened while driving. I think the van would have come to a screeching halt.
Mark
