1994 Mitsubishi Galant Electrical Drain

1994 MITSUBISHI GALANT
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RJMRCSD
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Electrical problem
1994 Mitsubishi Galant 4 cyl Front Wheel Drive Manual
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My car recently died, I jump started it and put a volt meter on it and realized the alternator was not charging. I took it off and had it tested at 2 different places, it failed at both. I replaced it, and started the car back up, put the meter on it alternator was charging. Was fine overnight, started up in the morning went about my business. I stopped, played a round of golf, 5 hours later, car wouldn't start. Jumped it it started up, I figured since the battery was drained a few times, plus it was old, and I live in arizona, the battery was toast. Replaced the battery, started up fine, put a volt meter on it again, alternator was charging it still. Went to start it this morning, and it won't start. There is some sort of electrical drain on the system.

Is their a good place to start chasing this. I don't have alot of cash to throw at this, but I'm good with cars and electronics, I know how the systems work, just not sure where to start looking on this car. Any help would be greatly appreciated.
Jun 17, 2008 at 11:28 AM
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DOCFIXIT
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Checking for drain is the right thing to do. Remove Pos. batt.cable place amp meter in series on 10amp scale. Have door closed any other acc. turned off. Observe meter should not be more than .5 amp drain if higher start pulling fuseswhen it drops you know know the circuit. Check wiring diagram then go componet to componet disconecting til it drops and there you have the culprit.
Hope this helps
Let me know
Note when on 10 amp scale if you read low switch to low scale for test the 10amp setting to protect meter until you know how big drain is.
Jun 17, 2008 at 11:52 AM
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RJMRCSD
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I did all these steps and when I hooked up my meter I was showing about 3 amps. Unplugged all the fuses and relays, under the hood, one at a time and nothing changed. I did the same with the under dash fuses with no change. The only 2 I couldn't do was a 60 amp fuse, one of the screw in ones, just a pain and my alternator one which is the same style. So I un-hooked the power cable to the alternator, and the amps dropped to .1, I don't know on this car if the alternator should be drawing 3 amps when the key isn't on but it doesn't seem right to me.
Jun 18, 2008 at 6:10 PM
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RJMRCSD
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I did a lil test of my own on top of this I started the car, let it run for about 20 minutes, the voltage when it started was 12.8 across the batt terminals, 20 min later, with nothing running on the inside the car at idle, it dropped to 12.2 and seemed to be slowly dropping the whole time, if you revved the car it would go up to 13.3, I unhooked the alternator power cable and am going to wait for an hour or so to check the voltage and see if it doesn't drop to see if my problem is in the alt wiring or the alternator itself.
Jun 18, 2008 at 6:46 PM
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DOCFIXIT
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The alt. should not draw 3amps. probably a diode in retifier bridge is bad. Would no show up on alt test.
Good luck you are on it
Jun 19, 2008 at 7:38 AM
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RJMRCSD
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I don't know if you have any handy but On my car its a 94 galant, dohc, the wiring that goes to the alternator, you have to 2 wires that go to the connector that plugs in, you have the battery cable, then you also have the wire that goes to the oil pressure sender, and theres another one, looking at my car its unhooked. I believe its a ground of some sort. but i don't know where it goes. If you have a diagram can you take a look and let me know. I put my meter on the positive batt terminal, the to that wire, and I read the batt voltage. so I know its a ground, I don't know if this is the reason for my problems.
Jun 19, 2008 at 11:04 PM