No starting again????

[1515art]

Jumped in my Jeep trying to make a pizza run and the dash lit up but the engine wouldn't spin. Pulled the relay and I can crank the engine jumping pin 30 and pin 87 but no start with the ignition on. The ignition switch has been a little funky as I can pull the key out sometimes when it should be held tight and the automatic transmission inter lock may be out of adjustment my transmission selector is only locked when the ignition is on and my foot is off the brake pedal. I was able to start it one time after disconnecting the battery for 30 seconds but the battery disconnect trick may have been just a coincidence as that only worked once. The actuator pin was changed 6 months ago, and it should have started when I jumped the relay if it was the aviator pin. I’m still thinking ignition switch related, I do have a back-up pcm if I need to check that. Guess I’ll be playing with my Jeep in the morning.

 

[1515art]

Good news I suppose put in the old PCM and no change turn the key and lights come on all gages seem ok, put new PCM back in I’m now pretty sure it’s not the computer. The engine will crank jumping the relay ignition on still no start this should eliminate the actuator pin? Going to check for a switch inline with the transmission interlock at the ignition switch and the ignition switch itself.

Been reading about a pk/or wire from the ignition sending power to the pcm although it seems the pcm is functioning unless the ignition power in question is a separate specific source into the pcm. I’m just digging into the ignition wiring and trying to understand where power is going but I’m still a bit confused where I should be getting power and why I’m not, hopefully it’s obvious when I’m holding the two switches in my hand a can put a meter on some of the wires.

 

[1515art]

My mistake it was the pcm, I forgot to put the relay back in when testing the old pcm, checked it again with the starter relay in place (how stupid I am) and it fired right up fine.

 

[1515art]

The tj is starting now switched the new pcm with the old pcm and it started I put the old pcm back in to check after it had been out for a while and now they are both working? Jeep starts fine for now, so just have to wait and see?

 

[1515art]

I have a question, I was under the impression if the ignition was on and with the starter relay pulled out that jumping pin 30 & 87 would start the engine? My Jeep will now start with the relay in, but will only turn over with the ignition on jumping the relay, what am I missing?