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Discussion Starter #1
Battery is new, alternator is new, belts, pulley's new. PCM was sent out for repair, said it couldn't be repaired due to robot installed chip, didn't give any indication of what was wrong. Car starts and runs, but reading no charge. I have 12 volts at alternator. Here's the funny part, reads 9 volts at field terminal wire, key on, engine off. With an Autel scanner I command a field circuit up to 50% and it doesn't change voltage. (While it shows 9 volts, it won't light a test light, and I checked 2 different volt meters to see if I was nuts). Very illogical. With 9 volts it should light the test light. I have continuity between the two small wires on the field connector all the way to their respective connectors that plug into the PCM. With this being said, a PCM should be my problem, correct? Or did I miss something?
 

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Battery is new, alternator is new, belts, pulley's new. PCM was sent out for repair, said it couldn't be repaired due to robot installed chip, didn't give any indication of what was wrong. Car starts and runs, but reading no charge. I have 12 volts at alternator. Here's the funny part, reads 9 volts at field terminal wire, key on, engine off. With an Autel scanner I command a field circuit up to 50% and it doesn't change voltage. (While it shows 9 volts, it won't light a test light, and I checked 2 different volt meters to see if I was nuts). Very illogical. With 9 volts it should light the test light. I have continuity between the two small wires on the field connector all the way to their respective connectors that plug into the PCM. With this being said, a PCM should be my problem, correct? Or did I miss something?
Seems like it.

To test it, unplug the field wire terminal on the back of the alternator. Then ground one of the field terminals on the back of the alternator, carefuly jump the other terminal to the positive side of the battery. Quickly after that start the engine. If your PCM is faulty, the alternator should be charging at full blast now (unregulated).

If your alternator is working now, your PCM needs to be replaced.

Another option would be to install a external voltage regulator (about $60.00 fix).

Good luck.
 

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Discussion Starter #3
Bought an external regulator and hooked it up, alternator charged but then overcharged, so I shut the car off because it was trying to shut itself off. Thought maybe the cheapo regulator was bad so I exchanged it, wired it in and same problem. Keeps charging and car tries to shut off to prevent overcharging. Alternator is capable of charging, so my guess is the PCM is bad. Ordered a new one from Chrysler and will have them install it and reprogram, for about $625 total. Sucks, but my wife really wants her car back.
 

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Bought an external regulator and hooked it up, alternator charged but then overcharged, so I shut the car off because it was trying to shut itself off. Thought maybe the cheapo regulator was bad so I exchanged it, wired it in and same problem. Keeps charging and car tries to shut off to prevent overcharging. Alternator is capable of charging, so my guess is the PCM is bad. Ordered a new one from Chrysler and will have them install it and reprogram, for about $625 total. Sucks, but my wife really wants her car back.
Regulator was not property wired.
 

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Discussion Starter #5
Well it was connected as I would do in any normal vehicle with an external regulator, should I have done something different? Is there a thread with exact directions? I've been working on cars 30 years and based on my knowledge and experience, the way I wired it in was exactly how it should work. If I missed something, please let me know what it is or if you know how it should be wired, I'd love to save $600
 

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Don't rule out a defective alternator even if new.....

I'm currently in the process of returning an alternator on warranty that I installed brand new (not re-man) on my friends MDX last December, old one stopped charging.

Since then he's been getting occasional power shut down/low battery (brand new). When I boosted and tested it charged well, everything seemed perfect. I changed the terminals, brass HD, soldered to cables. No problem with voltage drop test pos.+neg. Changed ignition switch also (worn).

Last weekend it shut down again, when I boosted and tested it seemed fine at first then I saw a big puff of smoke and alternator started whining and overheating and suddenly no charge at all.

My point: we wasted a lot of time and trouble (and $) assuming the new alternator could not be the problem. It was.

(it was an Ultra Power)
 

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Well it was connected as I would do in any normal vehicle with an external regulator, should I have done something different? Is there a thread with exact directions? I've been working on cars 30 years and based on my knowledge and experience, the way I wired it in was exactly how it should work. If I missed something, please let me know what it is or if you know how it should be wired, I'd love to save $600
To make it easier for you:



Direct Link: EXTERNAL REGULATOR

Note from manufacturer:

NOTE: The External Voltage Regulator Kit may also require a modified driver on newer ( aprox 06 & newer, some do, some don't need it) Dodge, Chrysler, Jeep vehicles Not Sure if your vehicle requires a modified driver?, Call 1-616-785-7990!
 

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Discussion Starter #8
I have everything in that kit except the FRM, so it would be useless to buy a kit. I wired it in as I would have an old chevy pickup, so if there is something different about how it should be wired, that is the missing piece. I found a few other sites late last night about it so I'll check them out.
 

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If your alternator is working, then there is no reason why the voltage regulator is not "regulating". How about the modified driver? Call those guys, they will definitely tell you what the problem is. You are just one call away. FRM shouldn't make a difference.

Regulator should be grounded or it wouldn't work.
 
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