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Hello, my name is***** sounds like you probably have a wiring problem going to alternator. Check voltage on both small terminals at the back of the alternator. If both have B+, ground the Dark Green wire at pin 10 of the center Powertrain Control Module (PCM) connector to see if it charges, if not the dark green wire is probably broken. While grounding pin 10 check to see if dark green wire at alternator is grounded, if not run a new wire between alternator and PCM. Let me know how it goes or if you have more questions, thanks.
Did alternator charge when grounding dark green wire?
You can use a paperclip to backprobe connector at alternator so you can ground wire. Let me know how it goes, thanks.
Voltage should be closer to 14, alternator does not appear to be working at all. Does large wire going to alternator have battery voltage?
The dark green/orange wire should have power and the dark green should have ground. Check to see if dark green has voltage at alternator, if not check to see if there is voltage at pin C25 with vehicle running. Let me know, thanks.
If you have voltage at PCM but not alternator it sounds like wiring problem, run new wire between alternator and PCM. Let me know how it goes or if you run into more questions, thanks.
If you have good power on dark green/orange wire but alternator is not charging when grounding dark green wire that points toward alternator. Only other thing it can be is a problem with case ground on alternator. Let me know how it goes or if you have more questions, thanks.
Case gets ground through mounts. You can use ground on case and battery + to check voltage, if readings is good you know case ground is good. Let me know how it goes, thanks.
If your sure alternator is getting good power on green/orange wire but grounding dark green wire doesn't help then problem is definitely alternator. For alternator to work it needs good case ground, ground on dark green, and power on green/orange...Then it sends power to battery on large wire. Let me know how it goes, thanks.
That doesn't tell if the alternator is bad but will tell you if alternator isn't working. But the alternator can stop working for many reasons so that test wouldn't do much. If your 100% sure green/orange has power and jumping dark green to ground doesn't activate alternator then I would replace again. Let me know how it goes, thanks.