Alternator problem? Regulator? Wiring? Connector? HELP!
03-07-2009, 07:50 PM
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Alternator problem? Regulator? Wiring? Connector? HELP! OK, about 4 months ago, while sitting in my driveway, my voltage droppeed to about 9 volts and stayed there till I killed it and started it back up in the morning, and then it was fine! I've noticed that over the past 2 months that my lights dim and fluctuate in conjunction with rpm and every once in a while my voltage would go WAY low and then go right back up to 14 volts! The other day, it went down and did NOT come back up, and eventually I just flat out died on the way home. Did my alternator just take a crap or what? Could it be the voltage reg.? I doubt it would be the wiring but you never know. My battery is only 4 months old. WHAT COULD IT BE? I don't want to go spend money on something useless... PLEASE HELP!
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03-09-2009, 06:42 PM
#13
The exciter wire won't always throw a code readable with an autozone scanner.
I have the one they use, and I have hp tuners. HP Tuners shows it.
The exciter wire is a thin gage wire that goes straight to the ecm with no splices or anything. It basically turns the alternator on. IIRC it sends out 10 volts to turn it on, if the voltage is low or there is none a good alternator won't work either.
The best thing you can do is connect a volt meter to the exciter wire, if it has around 10 volts with the engine running then the alternator is bad. If the wire has zero volts, either the wire or the ecm is bad.
I have the one they use, and I have hp tuners. HP Tuners shows it.
The exciter wire is a thin gage wire that goes straight to the ecm with no splices or anything. It basically turns the alternator on. IIRC it sends out 10 volts to turn it on, if the voltage is low or there is none a good alternator won't work either.
The best thing you can do is connect a volt meter to the exciter wire, if it has around 10 volts with the engine running then the alternator is bad. If the wire has zero volts, either the wire or the ecm is bad.
03-10-2009, 03:36 PM
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I had a similar problem as to the one you described. I thought it was the alternator too. Then I looked at the wire that connects to the alternator at the bottom (I believe the red 12V wire), and it was somehow destroyed. That wire was hanging on by like 3 copper strands. I still removed the alternator and got it tested. As I suspected it was fine, and so I just repaired the power wire to the alternator.
Don't forget to look at all the wiring to the alternator as well. The exciter wire is one, and the 12V wire is the other. If in doubt, get the alternator tested just like I did.
Don't forget to look at all the wiring to the alternator as well. The exciter wire is one, and the 12V wire is the other. If in doubt, get the alternator tested just like I did.
03-13-2009, 10:28 PM
#17
