Chrysler Repair: 01 Sebring Conv. LXI 2.7 - No Spark, P0601, sebring conv, fuel pump relay

Question
The check engine light was on when I got the car so I scanned with a Snap-on scanner an got P0601 (Internal Control Module Memory Checksum error) but the car ran fine. About a week later it wouldn't start. It had no spark.I checked the scanner for cam & crank signals & it shows they are functioning properly. It even shows rpm reading during cranking. I even tried a PCM from my friend's 2001 Sebring Convertible. Same year & engine but her's is a Limited model not a LXI.I've also tried my other key & I don't have any flashing of the security light, it just comes on steady with the ignition on. Can you help please? I don't have a lot of hair left :)

Answer
Hi Charlie,
The P0601 shows the only remedy to be replacing the pcm. The security light staying on usually means that the anti-theft system is armed, which would also cause a no start, but usually that would be a monentary start followed by a die after a couple of seconds. But it is suspicious that it is 'on' and corroborates some sort of internal communication issue in the pcm assuming that you have tried to lock/unlock both front doors in order to 'clear' it. Start by checking fuses 23, 14 and 8.
Since you do have sensor signals, you could try jumping across the autoshutdown relay to get 12V to the coil for sure (84 to 82, are the pin numbers which should be shown in the socket, I believe) but in any case from front to back of the relay socket) and then see if it will spark.  If so, but it still won't start, then jump the fuel pump relay socket similarly (16 to 15) and try again. If that gets it running it will allow you to get parts, etc., but always disconnect the jumpers for safety and to save the battery, etc. I think you will want to replace the pcm and program it properly so as to defeat the theft system and re-establish any other necessary communication between the pcm/tcm/body computer.
Roland