Okay, I have a 1993 Jeep Grand Cherokee.. 5.2 L All Time 4-wheel drive.
At first it started having issues with charging. But it was still running at least..
So I was driving one night, and the car just died. Tried to start it up, and now I had no spark. Coil was bad. Changed the coil. Got it running again, but still wasnt charging. The gauge for battery was in the RED, I tried knocking on the alternator, and it made the gauge go back up..
Went inside the car to get a tool or something, my friend decided that he was gonna "try" to help me out, by looking under the hood, unknown to me at the time.. Well I guess he touched the screws, on the back/bottom of the alternator, together with a wrench or something, and shorted something out. (positive & negative screws, i think)..
No spark once again. So I got another coil, and this time.. No Spark. Then I tried a new Pickup Coil also.. Still no spark..So I changed the alternator. And now, still no spark..
So.. Anyone have any ideas of what I could try next? You think that maybe my friend shorted out the computer in the Jeep?
Appreciate any help..

 

Yeah, you are right. The PCM controls the alternators output by sensing system voltage and battery temp. He probably toasted the PCM. You probably had worn brushes in the alternator, but now I'd be willing to bet it's the PCM. Head slap your friend!

 

Believe Me, I Did More Than.Smack My Friend.. I can't Believe What A Moron He Is.. But I Guess The Problem, I Thought It Was, Just Might Be Then. I Appreciate You Responding & Taking The Time To Help Me Out. Guess It's Time For Me To Now Spend More Money, And Get A PCM. Just had The Transmission Rebuilt Not Too Long Ago. Wasn't Prepared To Have To Fork Out More Money again so soon.. Guess I Can't Expect Much From A Car I Got For Only $500. (from a friend, as-is).. Which I kinda knew it needed work.. Just not one thing after the other, after the other.. Blah blah.. So soon.. Ooh well..
One Quick question... For anyone who has a 93 Jeep cherokee.. Not sure if all Jeeps are the same.. But the lighting thing on the ceiling of the car.. Where the keyless door entry sensor is & Alarm thing.. Or whatever.. Is the sensors for the keyless entry clocks thing, is that infrared? Isn't that what you point the clicker at & that's how u look the doors & set the alarm & stuff? That's up in the ceiling light thingy, correct?.. Is there somewhere to get another one or how would I go about fixing that??
Don't ask, but a friend of mine, years and years ago, before the car was actually mine, he was driving it and thought the little black thing that was up on the ceiling light, he thought it was a camera & he ripped it down & broke the little circuit board up there that was for the keyless entry/Alarm.. So since then, no clicker & no way to set the alarm & all that good stuff..
Can I but another circuit board/infrared thing to put up there, or is that kind of a loss cause? Don't wanna spend a ton.. Maybe find one at a Jeep in one of those pick apart yards? Any suggestions??
Sorry for such a long response.. Appreciate you & any/every one else, taking the time to read this & help me out.. Thanks in advance!!

 

Check ALL of your fuses before spending any cash on a new PCM.

 

I just had someone put the charger in backwards and it blew this fuse. I also just replaced my alternator and did a bit of rewiring. Are you pumping the gas? Maybe don't. Now that I have everything just about back to running properly I found it will turn over, even after 5 or more times trying if I don't touch the gas, (flooding can seem like no spark). I also changed my battery connectors because one was loose and worn out. Process of elimination, and start with the cheapest solution first, that's my advice. Good luck.