i have a 1994 Cherokee sport, and it will not start.when you turn the key it will crank and just not start, for some reason the ecm is not sending a signal to the auto-shutdown relay to tell it to let the truck start. iv replaced the crankshaft sensor and the auto-shutdown relay, checked the cables and plugs that are in the pathway of the signal and got nothing. any advice?

 

Go by wiring diagram:
check all relay connectors for + and ground
you can use jumper in relay connector.
Get test light and multitester.
If you don't understand wiring diagram, stare at it until you do.
It is pretty simple. I am in process of repairing TV first time in my life, trust me, automotive diagrams are easy.

 

Have you checked to see if there is power to the ASD relay coil with the key on? I believe the PCM supplies the ground to operate it. Fuses, etc....

It should operate for about 5 seconds even without the crank sensor input, it has to for the vehicle to start.

 

to the first guy: their part of my job

to the second guy: i have checked and i have no signal there at all.

 

If there's no power to the ASD relay, have you checked the appropriate fuse?

 

Check codes b4 throwing parts at it ....key on key off thats what this functions for .....

 

I had the same issue a few weeks back, it was a bad ECM, replaced it with one reman by Chrysler, problem solved but it cost me a few $.

Good luck

 

i did no codes came up before i "started throwing parts" at it

 

No 12 or 55 at least ?

 

to free: a 55 and from what i found that means everything is good right?

 

means end of test.

 

Checked all fuses yet ?

 

Also remove dist cap my 94 just died one day removed the cap and the cam sensor had self destructed i replaced it and it fired rite up . just a thought.