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Blown Fuel pump and ECM fuse when tank is mounted!

Thor86

New Member
Ok this has stumped everyone I know. I just got a 04 Road King. The fuel pump and ECM fuse were blown so I replaced them and as soon as I turn the ignition on the pump blew again. Sometimes its the pump fuse and sometimes the ECM never both at once. Here is where the fun begins! If I unplug the pump at the top of the tank the fuses are fine. I checked the wires in the tank and they check out and also put a new pump in. But still blows fuses. Now ive pulled the tank and checked over the harness and found no issues. Set the tank back on plugged the pump in and the fuses were fine. BUT! If I put a single mounting bolt on the tank just finger tight the fuses pop. No bolts and fuses are fine. Please help!!!
 
Seems to me , that the pump (wiring) has a short . You said fuse blew when I put a bolt in. This bolt grounds the tank to the frame then!.
Maybe stupid idea , but are the fuses the correct ones , check values in the manual. The pump draws quit a lot of power !.

Good luck .
 
Have to agree with Roadking-1960, sure sounds like a short somewhere. It doesn't take much of a bare wire rub to short out and blow a fuse. I can't think of any other reason a fuse would pop when power is applied.
Have you washed it lately? I've heard water getting into the on/off switch can cause corrosion and other issues as well.
 
Seems to me , that the pump (wiring) has a short . You said fuse blew when I put a bolt in. This bolt grounds the tank to the frame then!.
Maybe stupid idea , but are the fuses the correct ones , check values in the manual. The pump draws quit a lot of power !.

Good luck .
It calls for 15 amp on both the pump and ECM fuses and I have checked the wiring in the tank with a multimeter and didnt see any obvious issue but I will inspect it again. Thank you.

Have to agree with Roadking-1960, sure sounds like a short somewhere. It doesn't take much of a bare wire rub to short out and blow a fuse. I can't think of any other reason a fuse would pop when power is applied.
Have you washed it lately? I've heard water getting into the on/off switch can cause corrosion and other issues as well.

It might have gotten a little rain on it about a week ago but its been in a garage ever since. I will check the switch just to be sure. Thank you!

Seems to me , that the pump (wiring) has a short . You said fuse blew when I put a bolt in. This bolt grounds the tank to the frame then!.
Maybe stupid idea , but are the fuses the correct ones , check values in the manual. The pump draws quit a lot of power !.

Good luck .
I will also take a closer look between the pump and the fuse because I agree something is grounding out just me and my more experienced friends cant figure out why. Again thank you!
 
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Set the tank back on plugged the pump in and the fuses were fine. BUT! If I put a single mounting bolt on the tank just finger tight the fuses pop. No bolts and fuses are fine. Please help!!!

something in the tank is "hot to ground". Try this....
Tank off bike, apply 12V to the connector at the tank top. Then take your volt meter and put the neg (-) on the negative of your 12V supply, then take the + (pos) meter lead and touch it on bare metal some where on the tank.
IF you measure 12V on the tank then something inside that tank is "hot to ground". Find what is hot and you probably will solve the fuse issue.
 
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