won't turn over,fuel pump continues to run after shutting key off

2004 CHEVROLET SUBURBAN
140,000 MILES
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KLHJAB
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replaced battery,started and ran to friends house 30mi. shut off. started and left there got home 10mi. next day won't turn over and when you return key to off position fuel pump will continue to run unless you pull relay. pulled starter spins fine when hooked to battery. security light goes out when switched on like it should. checked all ign. fuses. wtf?
Jul 21, 2013 at 12:37 PM
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JDL
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Do you only have one gas tank on this? My first thought is the fuel pump relay is faulty? Check other relays in your vehicle, if the same as fuel pump relay, swap the relay. If you still have same problem, then, it isn't the relay. You would need to check voltage and ground circuit for the relay.

Did you check voltage and ground at the starter, before you pulled it? I don't have your wiring right in front of me. Usually, one terminal at the starter goes hot with key in the crank position. The bat terminal at the starter, hot all the time. The crank feed usually goes through the neutral of clutch switch, depending on your tranny.
Jul 21, 2013 at 1:33 PM
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JDL
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Just to add, make sure the battery has a full charge. Any testing with starter bolted on, make sure tranny is in park or neutral and the parking brake is set.

Wanted to add the starter wiring.
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Jul 21, 2013 at 1:46 PM
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KLHJAB
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two tanks. have swapped relays,same results. also i had changed out oil pressure sender,don't see how it could have caused this though.
Jul 23, 2013 at 11:08 AM
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JDL
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Hope you got it fixed by now. With two tanks, my info shows to pumps, don't know with is running? I'd have to check voltage and ground for the relays, note the diagram. The computer controls ground for the relays.
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Mar 25, 2014 at 12:03 PM
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JDL
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Just to add, the info I looked at was for 5.3L vinT
Mar 25, 2014 at 12:04 PM
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