I purchased an 07 patriot yesterday after test driving it 3 times this week. Everything seemed be in working order, no problems. Today I get in and it won't start. I got a jump and it ran fine on the way to autozone but with the check engine light on. They tested the battery, it was fine. They plugged in their computer and it said to see manufacturer. It started up several times while I was there and then when I went to start it to leave, it needed a jump. It started fine with the jump and I was able to drive it home. Does anyone have any idea at all what is going on with this thing?? perhaps the starter? This is a nightmare!
They key statement I read that was immediately familiar was, "struggled to start". This was the exact symptom I've had before that required a PCM reset.
You may have a bad EPROM onboard your PCM (computer), bad wiring, connector, etc that may have perhaps caused something to go wrong when the computer was writing to memory. Based on my experiences, the computer in our Patriot is very sensitive. In the past (even before my Computer was Tuned) when I had my ScanGauge plugged in, I would on rare occasion for seemingly no reason see a strange DTC code relating to the PCM.
Like you, I had a similar problem starting the engine, where it was clearly 'struggling', so I wound up resetting the PCM. Afterwards, the Patriot started just fine and the PCM began the Adaptive Learning Mode. It easy to do, just follow the directions under the "Forced Flash" section here:
http://www.avengerforumz.com/showthread.php?t=40089
*Note: DO NOT touch the positive battery cable to the ground terminal on the battery. Instead, you need to touch (ground) the positive battery cable to a solid metal part of your vehicle's frame.