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Alternator not charging

Tiny
KARLKRIEGER
  • MEMBER
  • 2006 DODGE CHARGER
  • 5.7L
  • V8
  • 2WD
  • AUTOMATIC
  • 152,200 MILES
My alternator is not charging. I used a test light and have power to trunk fuse box, engine compartment fuse box and the starter but no charge at alternator. I am also getting three trouble codes, U0100 (lost communication with ECM/PCM A), U0103 (lost communication with gear shift control Module A) and U0121(Lost communication with Anti-Lock Brake System Control module). The charging issue and trouble codes started when I installed the starter and accidentally hooked up two wires wrong so when I hooked up the battery the positive cable got hot. I disconnected the battery quickly. Realized what I did and reconnected the starter wires correctly. So I figure I either fried my PCM or broke a fusible link to the alternator. So my question is, where is the alternator fusible link or do you think it is something else besides my that or the PCM? Thank you
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Sunday, June 17th, 2018 AT 2:38 AM

8 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 42,968 POSTS
It sounds like the PCM is not working or the power inputs are missing. Here is a wiring diagram so you can see how the alternator is wired and the PCM fuses so we can check those as well:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Check fuse #8 15 amp here are the fuse locations. With the key on make sure there is power at the fuses.

Check out the diagrams (below). Please run some tests and get back to us.

Cheers, Ken
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Monday, June 18th, 2018 AT 12:07 PM
Tiny
KARLKRIEGER
  • MEMBER
  • 7 POSTS
Okay Ken, here are the results from the fuse tests: (used a test light). Checking rear fuse box fuses with ignition on but engine not running, #8 15 amp fuse good, #29 5 amp fuse good. Oh just so you know I check both sides of all fuses for power. Front fuse box fuses with ignition on but engine not running, #6 15 amp fuse good, #9 15 amp fuse good, #10 5 amp fuse no power to fuse but fuse fine, #11 20 amp fuse good, #14 25 amp fuse no power but good when engine is running, #16 20 amp fuse no power but good when running, and #17, #20, #25, #27 fuses all good. So the red flag award goes to #10 5 amp fuse(power-train control module/starter) with no power going to fuse whatsoever. And for #14 and #16. I assume they are supposed to receive power when engine is running but not when engine is not running. So how should I go about fixing this? Ken, I appreciate you helping me trying to resolve this issue, thank you very much! Karl
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Monday, June 18th, 2018 AT 9:36 PM
Tiny
KARLKRIEGER
  • MEMBER
  • 7 POSTS
Oh, and #10 fuse still has no power when engine is running.
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Monday, June 18th, 2018 AT 9:39 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 42,968 POSTS
#10 says it is for a police version of your car here is the power distribution diagram so you can see. Can you do me a favor and using a test light can you see if the main charge lug on the alternator has power?

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Check out the diagrams (below). Please let us know what you find.

Cheers, Ken
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Tuesday, June 19th, 2018 AT 11:05 AM
Tiny
KARLKRIEGER
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  • 7 POSTS
No power at all at the main charge lug on the alternator.
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Tuesday, June 19th, 2018 AT 11:25 AM
Tiny
KEN L
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You found the problem, there should be power there at all times check the fusible link and look at the alternator wiring diagram above. Let me know what you find upload pictures of the problem would be way cool for anyone else that has this problem.
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Tuesday, June 19th, 2018 AT 1:53 PM
Tiny
KARLKRIEGER
  • MEMBER
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Ken, thank you so much for confirming what I suspected. I will post some pictures when I am done. Your awesome brother! Cheers to you, Karl
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Tuesday, June 19th, 2018 AT 4:29 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
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Looking forward to it :) let me know what happens brother.
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Wednesday, June 20th, 2018 AT 10:23 AM

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