1997 Chevrolet Venture fuel pump

1997 CHEVROLET VENTURE
149,000 MILES
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MIKE DREGER
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I am having trouble figuring out a fuel pump problem on my 1997 Chevy Venture. I have power to the hot side of the fuel pump relay but not from the relay side wire (Green/white) coming from the PCM. I do have power coming into the PCM (orange) wire and when I jump the orange and green/white I get power to my relay. I have tried another PCM and still the same result as my original PCM. My question "Is there another power feed within or to the PCM that would affect output power the the fuel pump relay?" A sensor? If so what is that sensor?
Jun 18, 2013 at 12:07 PM
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CARADIODOC
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Are you expecting to find that relay turning on when the ignition switch is on? It should not turn on unless the engine is rotating so you need to check it while cranking the engine.
Jun 19, 2013 at 12:11 AM
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MIKE DREGER
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I was expecting to find power with just the ignition switch and did not realize that I had to start to get power to the one side of the relay. I went home at lunch and tried your suggestion and found I did have power. I put the second PCM. back in and van started. Thank you.
Jun 19, 2013 at 2:45 PM
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CARADIODOC
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Dandy.

This is a Chrysler system and it's very effective and reliable. The idea is if a fuel line is ruptured in a crash, the engine can't run without fuel pressure, so it stalls. When the Engine Computer stops receiving pulses from the crankshaft position sensor and / or camshaft position sensor, it knows the engine has stopped rotating so it turns off the automatic shutdown relay, (Chrysler), or fuel pump relay. That turns off the fuel pump so it doesn't dump raw fuel on the ground creating a fire hazard.
Jun 20, 2013 at 1:11 AM