Sine Deviance
New member
Okay... I am having the weirdest problem ever. I'll just start at the beginning. Jeep is a '95 YJ with a 2.5L.
We're out of town for Christmas vacation. My Jeep's alternator apparently stopped charging and yesterday it went dead while I was driving it. Today I replaced the alternator and it didn't work. So I replaced the new alternator with another new one and again it didn't work, so it's not the alternators causing the problem. They both passed the bench test (the original alt did fail though.)
After alternator #3 I had them check it while the Jeep was running. Their little computer says that the cause of the charging system failure is that the voltage regulator has failed. I am to understand that the voltage regulator is on the PCM. I do not trust their little computer 100% because the Jeep otherwise runs fine, and it seems to me that if the PCM was shot it would be running in limp mode or wouldn't crank up at all. They also tested my battery and it was good. That was to be expected considering it's a new battery.
I checked all of the main fuses in the fuseblock under the hood. None of them are fried. They all passed a test light check.
Is there anything else I should check in the morning before I make the call to have it towed back to home? Do you guys think it's the PCM? Can I install an aftermarket voltage regulator and get this thing charging like it should?
Any help would be really appreciated, I'm kinda screwed right now. Thanks!
EDIT: Some extra stuff I forgot to add in (gotta love stress!) Before I even walked out the door with either of the new alternators I had them bench checked. They both passed. However, after I swapped the first new one for the second new one, they bench checked the first new one again and it failed the checks three times. So either that alternator was a bum alt off the shelf, or my Jeep somehow killed it.
We're out of town for Christmas vacation. My Jeep's alternator apparently stopped charging and yesterday it went dead while I was driving it. Today I replaced the alternator and it didn't work. So I replaced the new alternator with another new one and again it didn't work, so it's not the alternators causing the problem. They both passed the bench test (the original alt did fail though.)
After alternator #3 I had them check it while the Jeep was running. Their little computer says that the cause of the charging system failure is that the voltage regulator has failed. I am to understand that the voltage regulator is on the PCM. I do not trust their little computer 100% because the Jeep otherwise runs fine, and it seems to me that if the PCM was shot it would be running in limp mode or wouldn't crank up at all. They also tested my battery and it was good. That was to be expected considering it's a new battery.
I checked all of the main fuses in the fuseblock under the hood. None of them are fried. They all passed a test light check.
Is there anything else I should check in the morning before I make the call to have it towed back to home? Do you guys think it's the PCM? Can I install an aftermarket voltage regulator and get this thing charging like it should?
Any help would be really appreciated, I'm kinda screwed right now. Thanks!
EDIT: Some extra stuff I forgot to add in (gotta love stress!) Before I even walked out the door with either of the new alternators I had them bench checked. They both passed. However, after I swapped the first new one for the second new one, they bench checked the first new one again and it failed the checks three times. So either that alternator was a bum alt off the shelf, or my Jeep somehow killed it.
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