Bad PCM?

Hey everybody. New to the forum and looking for help. I have a 2000 xj with a 98 engine. Got a bad map sensor code. Swapped out several map sensors and still have the code. Checked the plug and found that I'm getting 5.3 on the power lead and 5.2 on the signal line with the ignition in run position. Also getting the same on cam, crank and tps. Checked the harness. Had melted wires. Repaired wires and rewrapped the harness. Still the problem remains. Fuses are good. Relays are good
Grounds are good. Any suggestions on what to check next or is my pcm fried? I appreciate any advice.

have you reset the PCM yet?

Yes. After each map threw a code as well as after the harness repairs

When my 2000 wiring started melting down I lost one of the injector drivers in the PCM.

What is the exact CEL Trouble Code number or numbers ?

All the OBD-II engine sensors use 5 volts.

Failure of the PCM is very unlikely and should only be considered after a thorough and in-depth diagnostics and trouble shooting for the trouble codes observed. If the PCM can't see data from an OBD engine sensor it can only assume sensor failure, it cannot see or check for wiring or wire plug issues.

I don't recall the number for the code. The guy with scanner just said bad map sensor. After 4 bad ones in a row I decided to check the plug situation. With the motor not running but key in run position the meter showed 5.3 volts on the power lead, 5.1/5.2 on the sensor return line and 0 the ground. That's with sensor unplugged. Cam, crank, tps and iac all show the same while unplugged. The symptons while running were running very rich, misfires, backfires and erratic shifting. I already inspected/ repaired damaged wires going to previously mentioned sensors as well as others in the same harness. Other than the pcm, is there any other part or electrical line that these sensors would have in common?Should I check wires going to the fuse box in the cabin or going to the transmission? Sorry if my terminology is incorrect... I'm kinda new to electrical issues. Thanks again guys for the help.

I suggest you start with a genuine Jeep Service Manual from www.pacificcoastmanuals.com or a subscription to Mitchell DIY.


Here is some reading materials
>> www.700r4transmissionhq.com/p0108-jeep-cherokee/
>> https://troubleshootmyvehicle.com/jeep/4.0L/how-to-test-the-map-sensor-1