Fuse keeps blowing

[CivicEater]

I replaced the fuse to the fuel pump but the car still didnt start... I think and think then go back and recheck the fuse and its blown again.....what would make this FP fuse keep blowing?

 

[AznStanger3v]

BAD GROUND!

 

[CivicEater]

but I havent touched anything in the engine since well before this started......woudlnt the bad ground have done this earlier?

 

[CivicEater]

I read in some old posts on stangent I was looking through that the CCRM could cause this....sound right or not really....I am gonna look for a bad ground but I cant think for the life of me where one would be....

 

[mo_dingo]

Follow the wires all the way from the fuel pump, to the chassis wiring harness. It will be a PITA, but you need to do it. I hate electrical work sometimes.

My guess is some of the insulation has worn off. Be very meticulous, examining each spot very carefully! Good luck! Glad to see you found the problem.
Scott

 

[CivicEater]

chassis wiring harness would be which one?

 

[AznStanger3v]

chassis wiring harness would be which one?

the one with the wire from the fuel pump is with if its a ccrm, ill help you out with one. i have a perfectly good one that i was gonna sell to seth5.0, but his engine problems were way more severe. but, start with the wires. my dad drills into my head that
Blown fuses = ****ty ground

thats for most cases. others are overloading and what-not

 

[mo_dingo]

Well, usually it's a short to ground. But it also could be a short to positive. Either way, one of the fuel pump wires is probably bad.

Could the short be in the fuel pump? Just a thought.
Scott

 

[5.0 from 95]

Not to flame anybody, but a blown fuse is not from a bad ground. There has to be 2 things present on a circuit, a + and a -. If the + or - is not there it just will not work. If the - touches bare metal, no problem because the metal on the car is a ground or is the ground. If the + touches the metal on the car, you get a blown fuse. If the load is pulling to many amps, blown fuse. If the load has a problem, blown fuse. Blowing fuses is how you are told there is a problem not there is a bad ground.


Paul

 

[CivicEater]

I am out there looking for a bad ground (or positive) now...what exactly am I looking for? a wire with the insulator rubbed off?

Wait now I just read the post above me....so there is also another electrcal problem to look for?

 

[DavidF]

Not to flame anybody, but a blown fuse is not from a bad ground. There has to be 2 things present on a circuit, a + and a -. If the + or - is not there it just will not work. If the - touches bare metal, no problem because the metal on the car is a ground or is the ground. If the + touches the metal on the car, you get a blown fuse. If the load is pulling to many amps, blown fuse. If the load has a problem, blown fuse. Blowing fuses is how you are told there is a problem not there is a bad ground.


Paul

Correct, in order to blow a fuse you have to have more current flowing then your fuse is rated at. If you have a bad ground it will stop the current from flowing, it will not allow more current to flow. Sadly I am haveing the same problem. As of now I havent found where it is shoring out. So for now I have ran a fused line from my battery to my fuel pump with a switch. Allowing me to turn my pump on manually so I can drive my car to work. As soon as I have time I will have to find the short.

 

[CivicEater]

Correct, in order to blow a fuse you have to have more current flowing then your fuse is rated at. If you have a bad ground it will stop the current from flowing, it will not allow more current to flow. Sadly I am haveing the same problem. As of now I havent found where it is shoring out. So for now I have ran a fused line from my battery to my fuel pump with a switch. Allowing me to turn my pump on manually so I can drive my car to work. As soon as I have time I will have to find the short.

That is a good idea becuase I need the car to get to work and class.....how do you make a "fused" line? what did you splice into? I was thinking the brown and pink wire going into the interia switch but I really dont know.....

 

[DavidF]

That is a good idea becuase I need the car to get to work and class.....how do you make a "fused" line? what did you splice into? I was thinking the brown and pink wire going into the interia switch but I really dont know.....

Yeah its the brown and pink one. I went to pep boys and bought a inline fuse holder and a 20amp fuse, along with a switch. I attached it the positive side of the battery and ran the line to the positive wire (brown & pink) of the pump. So just flip the switch to turn on and off the pump.

 

[CivicEater]

I dont have an inline fuse holder but I was just gonna solder the wire to the fuse....still work? At what point did you splice into the brown with the pink tracer? Under the car by the pump or by the interia switch?

 

[DavidF]

I dont have an inline fuse holder but I was just gonna solder the wire to the fuse....still work? At what point did you splice into the brown with the pink tracer? Under the car by the pump or by the interia switch?

Soldering A fuse will be fine. I was trouble shooting at the time so my tank was down. So I spliced close to the pump. But you can splice anywhere up the line until you come to where the short actually is. Thats what Im going to do anyway. (find where the short is)

 

[CivicEater]

I did what you just said and the pump kciks on fine, but the car still just keeps cranking.....My mechanic friend said since you are bypassing most of the power wire and passinf the PCM the injectors arent opening....how did you fix this?

 

[DavidF]

I did what you just said and the pump kciks on fine, but the car still just keeps cranking.....My mechanic friend said since you are bypassing most of the power wire and passinf the PCM the injectors arent opening....how did you fix this?

I didnt have to do anything else. Im checking the wire diagram now to see if the PCM can tell if the pump is on or not. I thought it just sent a signal out to turn the pump on without any feedback. Im not sure.I know that the PCM turns on a relay that then supplies power to the pump. Ill keep checking.

 

[CivicEater]

Thanks You, if you find something let me know becuase this is getting frusterating.....I finally get the pump to kick on and still just cranks.
ALSO
I checked and I am getting spark and I took the schrader valve cap off and fuel was pouring into the fuel rail so this is the only thing that makes sense.

 

[DavidF]

I checked the wire diagram, and it looks like the #8 pin (DK GRN/YEL) on the PCM is connected to the 12volt positive wire going to the pump. In my case after a few burnt fuses my fuel pump stopped working even though the last fuse I put in did not blow. So as of now I still have a 20amp fuse in, so maybe in my circuit the PCM is getting that signal. Now I have to say this; you can try to put a 12volt wire to the PCM, but you do this at your own risk, ask for a second opinon, I would hate it if I caused more damage to your car. If you have a manual please check it out.

 

[CivicEater]

since we have established the short is from the inertia switch to the PCM then is it possible to just put a whole new wire from the PCM to the inertia switch?<<(Is that what you are saying David?) Is it more complicated than I am assuming? Where excatly does the wire run? Say it starts out (the green wire) from the inertia switch, and it heads to the front of the car.....does it hit the PCM then the CCRM? or vice versa? and after it hits the second box where does it go? I am awful with diagrams and have been looking at them for a few days and just get more lost. Why would it be risky?