1999 Dodge Ram No b+ power to fuel pump

1999 DODGE RAM
132,000 MILES • V8 • 2WD • AUTOMATIC
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SIMEON9237
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My 2500 P/U will run is I pour gas in intake but cuts of when it runs out. "0" fuel pump pressure at fuel rail. 1st pulled fuel pump thinking it was bad but after testing with external 12v power, pump appears to working fine. Re0installed pump but again no pressure to fuel rail.

At key "On", I don't hear the pump priming so I thing I have an electrical problem. Checked relays for both fuel pump and Automatice Shut-off and they seem tio be working.

Are there any other electrical checks that can be done to determine root cause of lack of B+ volts.
Jun 8, 2010 at 12:43 PM
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INTERNETMECHANIC
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I'd check the voltage circuits to and from the fuel pump relay. Did you check for proper voltage and ground at the proper terminals at the fuel pump connector, engine cranking? At the fuel pump relay, terminal 30 is hot all the time. Terminal 86 is voltage for the coil side of relay, goes hot when you turn on the key. Terminal 85 is ground for the coil side of relay, controlled by the pcm. Terminal 87, when relay is energized, carries voltage to the fuel pump.


https://www.2carpros.com/forum/automotive_pictures/512072_dodge_2500_1.jpg

Jun 8, 2010 at 4:17 PM