2001 jeep grand Cherokee. Winter truck. Sat all summer. Went to start it a couple weeks ago and the battery was dead. Used my Chevy to jump it. Jeep fired right up and ran like a jeep. I parked it and the other day I went to start it again and now it fires and runs for a few seconds and then shuts down. I cleaned battery terminals, checked for broken wire in rubber boot on drivers door jam. Tried using key to lock and unlock drivers door (only 2 places to use key in it are drivers door and ignition) I only have one key and the key fob. I can hear fuel pump running and getting fuel at the fuel rail. I'm at a loss now. I can't see how the key could magically go bad like that.. please help!!!! Is there a REAL way to reset the security or SKIM system? Engine immobilizer
What fuses or relay's are associated with the immobilizer? What should I check next? Also I plugged obd scanner in and is showing Pending code p1686

 

With the P1686 code, the system is not recognizing the key because the reader isn't functioning. There's been discussions recently about static electric discharges messing up the SKIM code reader. IDK if this is your problem. I'm afraid it's time for a dealer diagnosis, problem being it'll have to be towed.

Welcome to CF!

 

I have the same issue with my 2001 Grand Cherokee.
Checked battery and connections etcetera with no change.
I then had wife start car and I sprayed starter fluid into air intake and it stayed running until I stopped spraying. Does this merely shut off the fuel and not the spark?
I am not getting the key lamp blinking or staying lit and have no other fault other than the P1686.
Is this the column module SKIM?