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Alternator is hot with a battery charger on

68EFIvert

Well-Known Member
I just got done we wiring my car within AAW harness. It went pretty smoothly and the car started up right away. I was very happy since I had a problem with the car starting right as I started to rewire. I thought it may be my fuel pump was bad since I replaced that when I rewired the car.

The car started up a couple times just fine but then I noticed my battery was dead and it wouldn't start. I have replaced the battery but the car still won't start now. I noticed when I have the battery charger on it the alternator is very hot. You can hardly hold your fingers on it for more than a couple seconds before it becomes very uncomfortable.

Is the alternator bad or could it be something else? I read the codes on the computer and they came back fine but I have had the battery out since it ran last.


Darreld
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My first thought is there is a diode problem if the current is going back through the alternator. Do a quick google search and you can find some simple tests for the diodes.
 
I ran a diode check and it looks like I am getting high numbers on both side of polarity. I have takes it off and will take it to the parts story tomorrow for testing. I hope that is it but I would be pretty frustrated since it only has a few hundred miles on it but out of warranty from tuff stuff. :(


Darreld
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or you have a short circuit or a huge current consumer.
You need to check you wires !!

ground strap OK ??
 
I had the alternator checked and all was fine. I will check my grounds and add an additional ground strap.


Darreld
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I got home and when the alternator was still off of the car I tried to start it and it fires fight up. I haven't done anything else but remove it. WTH? Is the alternator really bad or I guess it could be the harness that connects the EFI harness to the alternator?


Darreld
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I had the alternator checked today at another parts store and it showed problems. I ordered a new prowermaster alternator and will see if that fixes my problem. I am keeping my fingers crossed.


Darreld
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I think I found the problem. My EFI wiring harness has a battery connection instead of an ignition feed. That is an assumption on my part. I can't think of a reason why the regulator would need a constant power supply instead of only when the key is turned on. Am I right with that assumption?


Darreld
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Ignition systems should only be powered by key-on signals. Only clocks, cigarette lighters, radios, and *shudder* burglar alarms should be powered by the battery.
 
Thanks for the confirmation Midlife. I have it hooked up the right way now and am charging the battery. It is now cold to the touch and once it is done charging I will double check it is holding the charge.


Darreld
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Glad I could check your shorts before you set everything on fire.:D
 
It looks like I had other problems that may have lead to this issue. After I finished rewiring the car the battery kept going dead. I thought I narrowed it down to the alternator trigger but that was only a result of another problem. I had a significant draw from the EFI harness still and traced it down to a relay stuck in the open position. Last night I changed all the relays and the one in question ran the ECU, injectors and IAC. When I went to bed the voltage read 12.92v and when I checked this morning it was 12.90v. I think I have finally figured this out!!!!!!!!!

In the meantime I am changing over to a different fan controller. I put in a Derale unit that will control multiple fans and is adjustable. I can get rid of ht spaghetti wiring of the relays for that system.
 
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