Does not start and no have 5v reference in TPS?

1999 JEEP GRAND CHEROKEE
213,000 MILES
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JAIME CHAVIRA
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I'm looking for diagrams to check wiring engine sensors because my vehicle does not start and no have 5v reference in TPS, I'm find some short circuit.
Dec 26, 2022 at 3:12 PM
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STRAILER
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Good job checking the 5-volt reference. This is telling us whether the PCM is bad or there is no power to the PCM. So, let's check the fuse #19, #6, #26 and # 16 for power in the under-hood fuse panel, this guide can help. If those are okay, let's swap out the ASD relay which is under the hood in the fuse panel as well.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

and

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Check out the images (below). Please let us know what you find. We are interested to see what it is.

Dec 27, 2022 at 2:28 AM
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JAIME CHAVIRA
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Thank you, but I'll go ahead and check all the fuses that work and that will have a 12v signal, including the fuses inside the truck next to the steering wheel, since previously it had had an identical fault, but in this case, it was fuse #12 inside, in this case, everything is fine. The PCM has 12V and lands correctly.
When connecting the scanner, I have no communication with the PCM but with the other modules yes, this happened after I removed the engine and repaired it, when I reassembled it and started it, it only turned on and the key warning light came on and I checked the engine. what I am looking for is the electrical diagram of the circuits that control the motor to look for possible damage in the 5v circuit that could be shorted.
Dec 27, 2022 at 2:43 AM
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STRAILER
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Yep, good idea what size engine? Here are the engine wiring diagrams for the 4.7 and a guide to help you with the testing:

https://www.2carpros.com/articles/how-to-check-wiring

I am sure the 4.0 engine is similar. You might have a bad PCM. Check out the images (below). Please let us know what you find. We are interested to see what it is.
Dec 28, 2022 at 1:25 AM
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JAIME CHAVIRA
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I was able to find the fault, disconnect the 2 reference 5v signals, it turned out that the transmission connector that carried one of the 5v references had stripped cables and they were sticking the cables.
Dec 28, 2022 at 1:44 AM
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STRAILER
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Yep, that will do it good job on the repair. Use 2CarPros anytime, we are here to help. Please tell a friend.
Dec 29, 2022 at 5:41 AM
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