Okay folks, drove the XJ Monday when we had a small snow storm. Brought it home from work, pulled it in the garage. Went out this morning to take it out for a spin and hit the switch and the electric fan immediately started working. I then tried to start it and nothing. It will turn over fine but, will not start..

Has anyone had this issue or maybe knows what is going on? The fan cutting on really puzzles me..

 

Sounds like a loose PCM plug or connection.

But here, what will help you figure it out is to check for these 3 things.
Compression, spark, fuel.

 

Gotcha but, why would the fan cut on?

 

What else could could it be? I checked the PCM plugs and all looks good. Turn switch, rad fan runs, turns over fine but, no start!

 

I think that year the fan will come on if the coolant temp switch is disconnected or bad, or if the AC is on (defrost?)
Have you pulled a plug to see if you have spark? Does the fuel pump spin up when you turn the key on?

 

The odometer says "no bus" when the key is on..

 

No spark and I don't hear the fuel pump kicking in like I always hear. Fuel pump is my starting signal. I always waited till it cut off before I started it. I will crawl under and check to see if I have voltage going to the fuel pump.

So if no spark and no voltage to the pump. Does this point to the PCM?

 

No fuel pump relay/fuse would be next.

 

I checked all the fuses under the hood yesterday. No issues found there

 

Swapped ASD relay with fan relay, swapped fuel pump relay around also. Still no spark and no voltage to pump. Changing out CPS tomorrow and if that doesn't work. Going to load it on the trailer and haul it to the dealership..

 

CPS will be here Thursday. Got a better deal on Ebay than anywhere local and it's a Mopar part...I hope it works cause my 8.25 disc brake and Aussie install is ready to go in..

 

I have the exact same problem. I also have no CEL when I key on. I have tried EVERYTHING I can think of. Replace Crank sensor, check +5 volt signal, check CCD BUS 2.5v tore the entire truck apart and unplugged everything. Can't figure it out.

 

Do you have a problem starting or is it just the fan kicks on when the key is turned to RUN (ON)?

 

Doesn't run at all. No spark. No injectors.

 

Might be the CPS, but first swap the ASD relay with the Fan relay and see if it starts.