The day before leaving on our 9 hour drive to Bantam Jeep fest my check engine light decides to turn on. I pull out the old code reader and it shows p1607-PCM internal shutdown. Sounds serious enough so I start my research. I came up with solutions like needing new software loaded on computer to changing inn thermostat and coolant temp sensor. I decided to change the easiest simple things first and bought a coolant temp sensor @ autozone for $14. I cleared the codes and have driven over 500 miles since then. Is it safe to assume that was the problem or is it just a bandaid on something bigger? Has anyone recently dealt with similar issues? I usually don't stress about obvious repairs like alternators and batteries bc you will know immediately if you fixed the issue but this error code has too many possibilities? Thanks for the input.