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Discussion Starter · #1 ·
96' OHC V6, battery is discharging under normal driving conditions, replaced the alternator with one from the junkyard...it tested good (for what it's worth), replaced mega fuse, and battery is good, I'm still getting the same discharge condition...is the "new" alternator I grabbed also garbage? Or is there some B.S. problem hidden somewhere in the amazing lack of space back there?
 

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a bad ground strap will cause charging issues. test the alt while running on the car and see what the volt output is. then test underload... turn air on, radio, lights and check the volts again. that will let you know if the alt is bad. autozone checks them for free. but look at your ground straps and make sure they are still good.
 

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Charging

96' OHC V6, battery is discharging under normal driving conditions, replaced the alternator with one from the junkyard...it tested good (for what it's worth), replaced mega fuse, and battery is good, I'm still getting the same discharge condition...is the "new" alternator I grabbed also garbage? Or is there some B.S. problem hidden somewhere in the amazing lack of space back there?
According to my book, there are 3 fuses.
The mega 175 which you mentioned

Alternator fuse in same box 30A
Fuse 11 in I/P box 5A

Starting place.

-chart-
 

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+1 for the small 5A fuse. That powers the "excitation" of the alternator, it won't charge without that power source.
 

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Discussion Starter · #5 ·
What is the fuse called? Most of the 5A fuses look fine, I've done one of the "Big 3" but doubt that would have made any difference. Is it possible the GEM module completely took a dive? or would nothing interior light wise work if it did. I want this car to die...but I also can't let it...I'm getting really close to driving a long ways off of a short pier.
 

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Discussion Starter · #6 ·
Bump, and also:
5A fuse for the alternator and Air Bag(fuse 11) is good, 30A alternator fuse is good, Mega fuse is good, alternator cable is good, alternator is good, cable to battery is good. I'm trying to do diagnosis on the PCM and BCM side of the harness, but my wire colors are completely different from the diagrams posted here on the forum. Different year? I have a LT GRN/RED that is supposedly going to the 30A fuse in the engine bay fuse block, I attempted to test continuity from the alternator plug to the 30A fuse socket, I get a brief beep, but when testing Ohms, it either steadily increases from about 2k ohms to 2M ohms, or decreases...so I can't really trust that, I don't know if my meter is screwed up or what, or if that is telling me something.

The other plug is an ORG/LTBLU...if I remember right. I have no idea where this wire goes. It is heavier wire so I'm assuming that would be the battery sense wire from the PCM?

Any help would be grand.
 

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is the alt voltage output in normal range. you said it tested good at junk yard but whats the output while in the car? i would test with everything turned on to make sure. air, radio, lights etc...
 

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Discussion Starter · #8 ·
Alternator essentially puts out Zero volts, battery discharges faster with the more accessories powered up. Alternator tests fantastic, puts out 12-15 volts depending on load, and 40-140 amps or so.
 

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if you have a side terminal alt. then the problem is your voltage regulator on the right side fender area. i am assuming you have good voltage of the side term but none at battery. if that is the case then change regulator
 

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right sheila. the rear post alt has volt reg built in. also check and make sure the voltage reg is plugged in and has a clean connection
 

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ok so lets recap... alt is running 14+ coming out and its making it to battery from battery to mega dist block and coming out of block you have 14 + volts right??
 

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Discussion Starter · #14 ·
Alternator is putting out Zero power, battery discharges during regular engine idle, alternator and regulator tested good, alternator cable is good, mega fuse is good, 30A fuse is good, battery cable is good, battery is good, 5A interior fuse is good, bulb in instrument cluster still lights with KOEO. Zero power is being produced by the alternator. When the engine is running I can watch the voltage drop on the battery from around 13 down.
 

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ok.. so the things i can think of then are. 1- 5 amp excite fuse is bad. 2- corrosion on excite wire connecting to back of alt. 3- voltage regulator has bad connection 4- alt is not tighten down and making good ground. ( also while its running watch the belt and pulley and see if it spins constantly )
 

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orng and blue goes to 30 amp.. then goes to mega fuse
yellow and white goes to mega fuse. and the white and black im not sure. i know its a short wire and doesnt go far
 

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Discussion Starter · #20 ·
My diagrams show the LTGRN/RED wire going to the 30A fuse, might be where I'm going wrong...will try those.
 
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