Electrical/Alternator/ PCM

[David Ruozi]

Hey thanks for having me in the group. So my '08 Liberty burned up the alternator few nights ago, middle of nowhere southern oregon. Very few wreck yards around close enough for me to get to and I can't afford a brand new one at the moment. Need the jeep to get to work, left one jeep in Ohio and the '98 ZJ blew the transfer case on my recent 3k mile road trip.

The only alternator I could locate and afford was off of a liberty a few years younger, maybe 06 or 05, it has a different plug connection than my '08. I didn't have very high Hope's but I bought the alternator and cut the plug off of the old jeep and sliced it onto my wiring harness.

No charge.

But during this whole ordeal when the original alternator burned up, I was having every code, bell and whistle going off, like a severe short. And this has happened before without burning up the charging system, and then it went away and stopped.

Is it at all compatible to put one of those older alternators on a '08 KK?

If it is compatible I'm worried the PCM is fried and that's why it's not charging. I tested the outlet that was spliced into the jeep and was getting about 11.5V but it will not energize the alternator to charge the battery and I had the alternator tested it is goood.

 

[David Ruozi]

Hey thanks for having me in the group. So my '08 Liberty burned up the alternator few nights ago, middle of nowhere southern oregon. Very few wreck yards around close enough for me to get to and I can't afford a brand new one at the moment. Need the jeep to get to work, left one jeep in Ohio and the '98 ZJ blew the transfer case on my recent 3k mile road trip.

The only alternator I could locate and afford was off of a liberty a few years younger, maybe 06 or 05, it has a different plug connection than my '08. I didn't have very high Hope's but I bought the alternator and cut the plug off of the old jeep and sliced it onto my wiring harness.

No charge.

But during this whole ordeal when the original alternator burned up, I was having every code, bell and whistle going off, like a severe short. And this has happened before without burning up the charging system, and then it went away and stopped.

Is it at all compatible to put one of those older alternators on a '08 KK?

If it is compatible I'm worried the PCM is fried and that's why it's not charging. I tested the outlet that was spliced into the jeep and was getting about 11.5V but it will not energize the alternator to charge the battery and I had the alternator tested it is goood.

UPDATE: The alternator was not compatible.

Bought a remanufactured alternator year specific and installed...still no charge.

Found several small shorts in the wiring harness from the 02 censor forward lefthand side, yellow solenoid wire at the front of the block where the harness comes up and, 4 small ground wires ran from harness near fuse box forward underneath the battery tray where they were pinched tight and some broke, right next to the stud that mounts the tray. Fixed all shorts.

I did a hard reset on the computer, battery cables zip tied together for 6 or 8 hours

Hooked electrical and charging system back up, started jeep and got 14.60V at terminals FINALLY.

Ran around a while and no codes, no dashlights, and I swear it has better throttle response and a better shift with better MPG.

My theory is the shorts confused, but hopefully did not damage, the computer.

 

[LibertyTC]

Glad to hear you are up and charging again. Good work finding the wiring issues!

 

[Billwill]

You were lucky...the shorts probably shut everything down before the wires could blow.

We have to be careful with swapping Alternators between different models...some big changes made over various models as to the type of rectifier/voltage regulator used over the different models...some have external regulators!