P0601 code 2003 Jeep WJ

[dlundblad]

This is on my 2003 Jeep WJ. P0601 internal control module memory checksum error. Supposedly this means a failing ecm. My Jeep had the CEL last week. Ran fine, but battery voltage read low when I checked that evening. (12.6 or so.) Topped it off overnight with a maintainer and she was good the next AM.

CEL came back today. Once again, ran fine. Got home and let it idle outside while I took care of the dogs as I had to leave right away and came out to it surging. Tried moving it out of the way and it died. Restarted no problem, but wouldn’t idle. I held the peddle at 2000 rpm or so and it was fine. Ran okay immediately after. Parked it and there she sits.

I’m guessing alternator seeing how it ran fine while cruising down the road. What say you all? Thanks in advance.

 

[jeepman3071]

Have you checked the voltage with the jeep running to verify the alternator is charging?

 

[dlundblad]

Have you checked the voltage with the jeep running to verify the alternator is charging?

It’s been idling just fine for about 10 mins and I’m getting ~13.75v.

*just now turned it off. Had it idling 30 mins and still at ~13.75v.

 

[K2K2]

My '04 had weird stuff happening, turned out there was corrosion in the cables extending about 8" under the insulation. Once I replaced the bad cables, all was well.

So check the cables, AND the battery with a load test.

 

[grasscutter]

Is that the Chrysler Pentastar V6? That thing is famous for wearing out camshafts and cam followers. Causes all kinds of codes.

 

[clinebarger]

Those are known for failing ECM's, But modules in general need good voltage & don't like A/C Ripple from a bad diode/s in the Alternator.