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Anyone have a wiring diagram that shows the low pressure oil gauge? I'm wondering what else is on the same circuit.

My truck won't start and it doesn't register any pressure on the factory gauge in the dash, but according to my scanner the icp is reading 1600 while doing an extended crank. I'm wondering if the sensor could be shorting out something else.

It did finally pull a cam position open fault, but only after about 10 extended cranks.
 

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First the factory gauge is on a circuit by itself and doesn't even go thru the PCM. The PCM doesn't even know that gauge exists. The only oil pressure the PCM seas is the ICP reading min 500 psi for it to command the FICM to fire injectors.

If you are getting ICP of over 500 psi then your no fire condition is not oil related. It is either lack of fuel; Ficm issue or no sync between cam and crank sensors or no sync between pcm and ficm. If you monitor the correct pids with your scanner while cranking you will be able to see what is not happening and causeing the no start.
 

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I went back to the vehicle this morning and it still wouldn't start. The fuel bowl was full. I did 4-5 long cranks and it just wouldnt fire and the factory oil pressure gauge would not move even though I was registering 1600 on the icp. I wiggled the wiring harness and it finally fired up and drove 15 miles home with no problem.

I'm assuming there must be a short in the wiring harness somewhere. The short must be pulling down the voltage going to the low pressure oil switch. I guess I'll start with the wires going to the oil pressure switch and start tracing those back.

Thanks for the help
 
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