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tinkybigger 05-09-2013 05:21 PM

Cherokee won't start
My 1997 jeep Cherokee won't start, CPS check, PCM check. No spark, No Fuel into the cylinder, Only into fuel rail, all relays are good. What else could it be Please Help.

tinkybigger 05-09-2013 05:41 PM

Ok to get a little more descriptive. I have no check engine light on whatsoever. The Jeep won't self code at all. I had a friend use his scanner and got codes P1389, P0700, P0743, and P1694. All the relays are good and I just put a new starter, new battery, new water pump. I did not have the starting problem until after I changed the water pump and battery. I thought it was the PCM and ordered one off ebay that was programmed to my vehicle. I also know it is not the CPS because I got one at Auto Zone and tried and the car still wouldn't start. It cranks and cranks just won't start. I have also checked all the relays and they are working fine. Any ideas as to what could be wrong??

tjwalker 05-09-2013 05:53 PM

Follow your codes. Start with P1389 which is NO ASD RELAY OUTPUT VOLTAGE AT PCM.

How do you know all relays are good? Have you swapped? First thing to try is to try swapping the ASD relay in the power distribution with a non-critical relay like the e-fan. Without an ASD signal, you're dead in the water.
Spark: 12 volts from ignition switch to the ASD relay; when the key is first turned on the PCM provides a ground to the ASD relay to energize it, then the ASD relay passes 12 volts to the coil primary side. If no crank sensor signal is generated after a couple of seconds the PCM cuts the ground to the ASD relay (and fuel pump relay too) and that cuts power to the coil (and fuel pump). Key to START and once again the PCM energizes the ASD relay. Now, a critical element is the crank sensor--no signal from the crank sensor and the PCM won't trigger the coil to provide spark.

tinkybigger 05-13-2013 09:00 AM

I swapped relays, then just to be sure bought new ones, still nothing. Old starter relay had a ground wire attached to it that ran straight to the fender. When i disconnected it the starter died. Now no crank no nothing.

The time now is 01:46 AM.

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