wiring problem

[Livin_The_Dream05TJ]

So last week i had a alternator go up in smoke. Sent the alternator back and they going to replace it for free. But the problem is that i put an alternator in the jeep that i knew still worked and the jeep is not charging. When to old alternator went could it have efficted the smart charging system. I looked up online and found the syaytem was controled by the pcm. It is an 05 wrangler. Recent add on was a new electric fan. Looked over the wiring for the fan and the wiring looks the be wired right.

[Livin_The_Dream05TJ]

OK so after tracing the wires i found that a wire had burnt though. Spliced the wire together and jeep is now charging. But now it is over charging. What would be cause the jeep to over charge now? Would the regulater in the pcm still be the cuase problem that made the last alternator go?

[Carl McFly]

When you say it's overcharging, what are you basing that on? DVM across your terminals, while it's running? I'm no authority on 2005 charging circuits but on my 2K, I typically see 14VDC, +/- .5V, with my Heep running (using a DVM). When it's shut off, my Optima drops back to the 12V range. My understanding is if the battery is weak or discharged, the charge will increase to compensate for that

[nostaw]

If you have a burned wire something upstream from the wire may have been damaged. Do you know what wire burned?

JW

[Livin_The_Dream05TJ]

the alternator mire burnt right befor it went into the fuse box. Lte the jeep run for a while last night and it started charging fine when i think the battery become full charged. Turned all my lights on and blower motor on and alternator still was charging at 13.9. Going to let the jeep warm up tomorrow and see what happens when the engine fan turns on (electic fan just installed). So for right know i think i found the problem. But will soon find out.

[ZAEDOCK]

Automotive charging systems typically operate between 13-15 VDC.