hello, have no power to the fuel pump, tried jumping the relay out. no luck.. what could kill the power to the relay? will crank if you pour gas to tbi
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1997 Dodge Ram 1500 Question: no power to fuel pump
Answer #1ZeeTech May 10, 2011, 13:11Master
A blown fuse can kill the power to the relay.
Replymcmalco, May 10, 2011, 13:39Rookie
checked all the fuses, shoudnt there be some kind of power in the wiring harness with the key on going to the pump? can feel the relay click, and have even swapped it out with another
Johnny Mopar May 10, 2011, 13:51Master
The fuel pump relay is Fuse #3 (20amp) located in the Power Distribution Center (PDC) powers the fuel pump. The relays control circuit is powered by the PCM. If the control circuit is dead, PCM replacement is required.
Replymcmalco, May 10, 2011, 14:12Rookie
if the pcm is the problem, would it still make the relay click?
Answer #3cogcan May 10, 2011, 15:28Journeyman
relay uses fuse 9 -10A (click) in fuse box and 8 -20A (pump) in the power distribution center, so relay can click and still not work
Replymcmalco, May 10, 2011, 16:29Rookie
Really thankfull for all the help fellas. I know for sure that i have voltage coming from the pcm to my relay, and all my fuses are good, what i need to know is how is best way to check the relay? And does anyone know where i can get a wiring schematic so i can know which wires to replace going to the pump
ReplyZeeTech, May 10, 2011, 21:22Master
You can remove the relay and jump the terminal 30 and 87 in the relay socket and see if the pump will run.
Here you can find great repair manuals with step-by-step instructions, diagrams, parts locations and other important information here: http://bit.ly/mitchell_repair_manuals_online
Or here: http://bit.ly/AllData_Repair_Manuals_Online
Mitchell has easier diagrams to read.
ReplyVisitor, May 11, 2011, 06:56
Jumped the relay out, and still no power going to the pump
ReplyZeeTech, May 11, 2011, 11:09Master
Can you check under the relay block and see if there is any melted wiring?
If you remove the fuse #3 and check for power in the fuse socket, what you got? Is there battery voltage??
Replymcmalco, May 11, 2011, 16:05Rookie
the wires under the relay box have no visible damage, and the fuse slot #3 is not used on the truck. It says n/a. however fuse slot #9 is for the engine and it has 12.46 volts in the socket.
ReplyZeeTech, May 11, 2011, 17:13Master
Ok, I looking at a diagram and fuse #8 (20AMP) should be the feed to Fuel Pump relay, a red-white (RD-WT) wire( #30 at relay), from the relay to the pump it will be Dark Green-Black (DG-BK) #87 at relay.
Can you measure battery (B+) voltage at the relay socket #30 pin? (RD-WT) wire?
Just pull out the relay and check. If there is no B+ voltage the problem is with the feed circuit to or from the #8 fuse.
The control circuit is fed from the fuse #9 (10AMP) Light Green-Black (LG-B) wire to relay# 86 and control wire from ECM Brown-White (BR-WT) relay #85.
When you jump relay #30 and #87 the fuel pump should get power if there is B+ from fuse #8.
There is another relay, ASD relay, can you interchange that for another relay, which is not part of the fuel system, like a foglight, A/C or horn relay?
Replymcmalco, May 14, 2011, 09:40Rookie
ok. i now have power to the fuel pump connector, but it only comes on for a second or two. does anyone know if there is suppose to be constant voltage.? and if so, which two wires would i use to check with a meter?
Replym98, October 01, 2014, 14:05Rookie
you will have power for just a bit...then it will shut off....as long as it lights up when you turn on the key for a few seconds your good...