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Issues with Alternator & ECM

rod8990

New Member
Joined
Aug 18, 2022
Messages
2
Location
Rogers, AR
Hey guys,

First time posting anything. I wanted to see if you guys have any knowledge on Alternator, ECM issues. I checked my voltage to my battery before I started it.(in range 12.6v)
Next I started it up checked voltage again and it was about the same. Checked voltage to alternator, same as battery.I have bought and 2 alternators thinking that might be the problem, but of course it's not. I bought all new Jeep Cables from "Jeep Cables.com" and that didn't work. Also bypassed ECM with a voltage regulator, nothing. Checked my plug from Alternator to ECM with test light and it shows power.
Could it possibly be a bad ECM. Getting a little frustrated! Now, I am no mechanic by any means, Just went off a few Youtube videos. Any help would be greatly appreciated.

Thank you,
Mr. Frustrated
 
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DavidPLindsey

Member
Joined
Mar 5, 2022
Messages
50
Location
Franklinton, La.
Hey guys,

First time posting anything. I wanted to see if you guys have any knowledge on Alternator, ECM issues. I checked my voltage to my battery before I started it.(in range 12.6v)
Next I started it up checked voltage again and it was about the same. Checked voltage to alternator, same as battery.I have bought and 2 alternators thinking that might be the problem, but of course it's not. I bought all new Jeep Cables from "Jeep Cables.com" and that didn't work. Also bypassed ECM with a voltage regulator, nothing. Checked my plug from Alternator to ECM with test light and it shows power.
Could it possibly be a bad ECM. Getting a little frustrated! Now, I am no mechanic by any means, Just went off a few Youtube videos. Any help would be greatly appreciated.

Thank you,
Mr. Frustrated

Just seen thread, What is the poor thing doing or not doing? May God Bless;DL
 
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CharlesHS

TJ Expert
Supporting Member
Lifetime Supporting Member
Joined
Mar 10, 2020
Messages
4,990
Location
Jacksonville FL, Quezon Philippines
IF you have checked the condition of the alternator wiring to and from the PCM, the fusable link cable from the alternator to the PDC lug, replaced the alternator twice, the battery cables and terminals are clean/tight.
Since the PCM controls the charge rate of the alternator then I would X2 on contacting Mark @Wranglerfix who is the forums resident PCM expert.
 
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