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1998 Jeep Cherokee 4.0 4x4.
No start condition. Needle gauges non responsive. Gauge cluster indicator lights are functional.
I repaired several shorts along the sensor harness and am still finding low voltage from the 5 volt reference. I studied all of your videos and decided to use a last use technique of cutting one reference wire (from connector B the white connector) to see if there are additional shorts along that circuit. No change. I reconnected that wire and cut the other, also no change. I disconnected both 5 volt reference wires and measure the voltage and it still showed about half a volt.
My question is whether the 5 volt reference wires should be showing 5 volts with both cut?
Th grounds have been verified. My only thought at this point is a faulty PCM.
What are your thoughts?
Are you able to communicate with any modules with a scan tool? Do these use a CAN system? If so, you could see if you have 60ohms between the high and low lines with battery negative disconnected.
If you have checked power, ground and ignition signal are getting PCM, i would say you have a faulty PCM
Another test is to feed 5v (current controlled) directly to sensor lines. So you can measure current demand. Also feed every line with a test light (limiting current with a proper bulb).
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