Need help on a fuse that keeps blowing.

[ssgtwright-usmc]

I have one fuse that keeps blowing and I dont know what else that fuse feeds.
I know its a fuse that handles the fuel guage. I dont know if the blackout lights also use this fuse.
I can fill it up with gas and 20 minutes later it shows empty, blown fuse.
I have to replace that fuse every 2-3 days now.
Any suggestions at what other items I sould look at as in a short or ground.
Its tight at the fuel sensor/float.

 

[SmokeyDod]

It has to be a "short" somewhere along that wire. I would start at the fuel tank (since you indicate that it is tight at the "float" I assume you lower tank & remove the unit from tank). Just follow the wire all way back to where it goes into your fuse block. The wire could have scraped place (naked wire) and as it shakes and moves while driving it could be hitting the naked area. Check closely at point where wire comes from fuel tank and goes thru hole in frame of truck.

 

[ssgtwright-usmc]

Will do, I replaced the sending unit last year and havent drove it till now. First time driving(myself) in a year. Had a MC accident at the beginning of year and now I am more like myself again then I was a few months ago.
I will never ride a bike again.

 

[papercu]

I can fill it up with gas ??

Wait till night, turn ignition on, wiggle harness wiring until you see sparks? Wayne

 

[doghead]

I would guess your problem, is NOT on the sending unit side of the gauge, since the sending unit simply varies the resistance to ground( a dead short to ground at the sending unit should put the needle to empty).

Your problem should be on the power to the gauge end(make sense?).

 

[Warthog]

Looking at the electrical diagram from the TM 9-2320-289-20 Appendix F, Figure F-4.

The wire number from the fuel sender is Pink 30A. Following the wire, it goes thru a connection on Figure F-3 and reverts back to Figure F-4. The pink wire runs to Pin 18 on the instument cluster. Pin 18 on instrument cluster runs to the fuel gauge. The power for the fuel guage comes from pin #5. It is a black wire. It feeds other items also. I have not traced it down and it is not in the diagram.

Can you tell us which fuse blows? Wher is it located on the fuse block? Is it fuse #15

 

[ssgtwright-usmc]

If I go with the diagram from the main post it looks to be the Marker lights, 20 amps.

 

[doghead]

What main post? Can you give us a link? Do you have a thread already going about this problem?(why this post?)

 

[ssgtwright-usmc]

What main post? Can you give us a link? Do you have a thread already going about this problem?(why this post?)

The FAQ on top of the CUCV section, page 2 with the picture of where the fuses are located.

 

[doghead]

The FAQ on top of the CUCV section, page 2 with the picture of where the fuses are located.

Oh, now I got it!

 

[Warthog]

The fuse you are talking about is shown as a 5amp Courtesy Lamp on all of the TM diagrams. Possibly the picture of on page 2 is incorrect or the manual is incorrect.

The diagram shows the fuse feeding the headlight switch for the dome light. Check you dome light wires.

Can you tell us what type of CUCV you have so we can troubleshoot the diagrams? I enjoy connecting the dots........LOL. Also reverify that it is the fuse that is the forth row from the bottom and the second fuse from the left.