Power Control Module in Jeep

Our Jeep has been dying on us while slowing down or idling. It has also been lurching some when driving. Oddly enough, the engine light has been coming on and off, and when it is on, the Jeep runs fine, but when the light goes off, that is when the Jeep acts up. Initially, we were told that fixing the PCM would not fix the Jeep, but would only allow diagnostics. Today the mechanic called to say the Jeep is now fixed and doing fine just by fixing the PCM. Any ideas on this? Does the PCM only diagnose, or does it also affect how the Jeep runs? Any comments, suggestions, etc., would be very much appreciated! My husband doesn’t want to pick up the Jeep until he knows it is truly FIXED! Also, we have put so much money into this Jeep that my hubby is ready to fix, sell, and go back to nothing but Honda, Toyota, or Nissan. Anyone have opinions on Jeeps? He says never ever again. Thanks!

If they installed a new module, it should be fixed. The module controls and also allows for diagnosis.

While there are no guarantees, my experience with Toyota and Honda vehicles has been so positive I’d have a hard time shopping for anything else.

The PCM or, powertrain control module, is basically the brain for the engine. It does a lot of things besides just communicate what trouble it senses.

I suspect that when the engine warning light was on the PCM went into what is called the “limp home mode” or, open loop. When the light was out it then went into the closed loop mode and then some sort of problem made the engine run rough.


Question for you since you sound knowledgeable on Power Control Modules. I just purchased a 2007 Honda Civic with 3500km on it. Drove it home and it would not start again, back to dealership and am now being told its the PCM abd they will install a new one. Concern with me is, can the PCM go bad that quick, I have the option of getting purchasing price back, or am I over reacting and this was just a fluke. You can e-mail me at powerb@rogers.com. Thnaks so much