04 RX1 headlight fuse driving me nuts

[derbydriver7]

Ok so I put approx 400 miles on no issues...one day i popped headlight fuse...now it will pop what feels like whenever it wants. I have completely tore the whole harness from headlights all the way back 3 times now searching for even the slightest nick or even a crack, read forums about the problem in front under tool box and have checked that now probably 10 times, just today it popped three right in a row as soon as I would install so then I unplugged hi low beam switch and all sudden it ran 2-3 hours before popping again thought I had it narrowed down to switch, I also checked that main harness in handle bars where it could possibly be pinched from turning, heated shield is hooked directly to battery nothing else hooked into fuse box, original bulbs, has 20 amp fuse in not sure what's supposed to be in there, just about ready to put a paper clip in and look for smoke. Let me know if I am missing something or any more advice as this has me about to pull my hair out

 

[YammyRX1]

Do you have a heated shield or anything else wired into that circuit?

 

[derbydriver7]

Nope heated shield is wired direct to battery, previous owner tied into a wire that comes out of the SIG fuse right next to headlight it powers water temp gauge just for the heck of it since I couldn't find problem I took fuse out of that fuse link that was added didn't make diff of course. And of course to ice the cake a little better we now have about 8 inches on ground at home and only time i can ride is after work when it's dark

 

[low flying missile]

Nope heated shield is wired direct to battery, previous owner tied into a wire that comes out of the SIG fuse right next to headlight it powers water temp gauge just for the heck of it since I couldn't find problem I took fuse out of that fuse link that was added didn't make diff of course. And of course to ice the cake a little better we now have about 8 inches on ground at home and only time i can ride is after work when it's dark

It does sound like a short but since you have checked so carefully I'll say there isn't one. It could be a bad connection making and breaking the circuit rapidly. This causes a lot of current to flow and can blow a fuse. I would clean all plugs that connect to the headlights and would check the ignition switch connections and function of the switch. I believe you can switch the carb heater relay and the headlight relay to see if that might be the cause as well.

 

[jong22250]

Are u just visualy checking or using a multi meter? Easyiest way to find a short is doing a voltage drop test set the the meter to dc and touch one end to the light fuse other end to the power side of the lights with them unpluged it should read zero if its not shorted if its shorted it will read a small amout of voltage if its shorted start working ur way up the harnnes find the the next connector in line moveing off the fuse and check agian to the end of the light plug till u get zero volts once u get zero last section u checked is the issue even a kink in a wire can blow a fuse voltage drop is best way to find the issue good luck dont give up with a meter and some patiance u will find the issue

 

[jong22250]

Oh ur gonna have to supply battery volts to the fuse with a jumper as the lights dont come on till the sled is running and u gotta have power going threw the curcit to test

 

[derbydriver7]

Ok I am by all means the farthest from being an electrician, I was visually looking feeling for a nick crack any imperfection which I never found, when you say use a multimeter like you explained basically all I will be doing is supplying the wires 12v and checking to see if full 12v is arriving at other end of harness correct? Sorry kind of dumb on electrical side of motors

 

[steiner]

You may have a headlight bulb that is shorted out.

 

[derbydriver7]

Well i wondered that also steiner...any way to check that? Both look same high and lows

 

[steiner]

Unplug one at a time and run the sled. They are a simple H4 bulb from the factory.

 

[derbydriver7]

Oh ic and see if running the one or other will pop fuse? Also what's a factory bulb? These are Phillips and they are super bright, could it be they just too much bulb?

 

[steiner]

Oh ic and see if running the one or other will pop fuse? Also what's a factory bulb? These are Phillips and they are super bright, could it be they just too much bulb?

You mentioned you had original bulbs in your first post. Thot you had the factory still in the sled. They suck. The Philips may be better but they will not pop the fuse.
I have seen on very rare occasions where a bulb has had a dead short. Sometimes it comes and goes as you hit bumps and jostle the connections inside the bulb.

 

[derbydriver7]

I just assumed they were factory bulbs I never changed them, original owner never mentioned it when I bought sled from him, had wiring from bulbs to plugs under toolbox all apart again tonight and that's when i realized they were a Phillips bulb...I tried shaking twisting bending wires and plugs to act like hitting bumps have yet to be able to pop fuse when trying to, hopefully tomorrow night I can go a little deeper with a multi meter, kinda acts like maybe somethings getting wet then it pops it but yet then sometimes it may pop two in a row and next one will go for two hours so i don't know

 

[jong22250]

Not gonna see 12 volts the way i suggested testing ur looking for no volts this way and thats what u want think of the wire like a garden hose stick ur hand over the end and it increases pressuer that increase is what ur messuring this way so u might see .678 volts or a bit more that will let u know u have a issue it should read like .003 if theres no issues in the circut

 

[derbydriver7]

Oh ok I got Ya now ok I will give that a shot thanks!!