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Discussion Starter #1
Hello,

I need a mechanic help.

I have a shortage on my F4, because the one fuse keep blown. this fuse control the blinkers, rear brake and honk (7.5).

I used to be able to push start the bike with the shortage. But it might have drain the battery dry, so i can't push start no more.

So, here is the thing.

I wanted to search for the shortage and repair it.

Where do i start?
What is the normal protocol for a mechanic to search for the shortage?

Please provide instructions or reading materials or tools, what ever help me to do it properly.

i haven't ride the bike for a month now...and really like to get it back on the road before the Sac2Bay event.

Thanks in advance!

 

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You say the fuse which blows controls the horn, indicators and the rear brake light. I assume if you don't use any of these three, the bike runs OK?

You will need a A/Vo meter to check the various wires to see which one has a high resistance, (grounding to earth) but if you have no experience of this kind, I strongly suggest you contact an auto electrician. Wiring diagrams and manuals can be downloaded from this site. Another thought, do you have an alarm system fitted to the bike, this may be malfunctioning.
 

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Discussion Starter #4
Hi,

I do not have an alarm system. I have the PC3.

At first, when the fuse blown i can still press the start button and it would work. but then, the whole display would dis-appear from the odometer and speedometer and the starter button didn't work.

Does the owner manual have the wiring diagram?

Thanks.
 

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I think I can help....First, before starting the bike change the fuse. Lift the tail section and just over the battery but attached to the tail is a wire that makes a u-turn. This wire goes beneath the tail toward the tail light. This wire is probably getting crimped in the frame and you mat have severed it completely. If you severed it, splice and repair. Otherwise, between your fingers gently pinch the wire where it appears crimped. Then reinforce it with electric tape and remember to observe this wire everytime you close your tailsection..Almost forgot, but some spare fuses. Hope this helps.
 

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Reopropf said:
Oh James....

Diagnosing electrical problems, much less over the interwebthingy, is not my strongsuit! Where are all those EE's around here!!!

In my opinion, someone who doesn't know where to start should probably save themselves some serious time [read frustration!!!!] and let a pro do it.

Check all the obvious, if you don't find anything then hand it over to someone who can make a reasonably logical path at a diagnosis. Please let me know if you need wiring diagrams and include your model and year.

I've never heard of the problem drmasis describes but give it AND ALL OTHER OBVIOUS points of likelihood a good going over. I've had a bad battery blow fuses, I've had bad fuse, relay and plug contacts blow fuses - those are all easy things to try first. Since it's always the same fuse you can isolate the problem to that circuit - look at the flasher relay, flasher bulb, tail light, brake light and horn contacts. Maybe the horn wiring as it passes up to the nose is another possible friction point.

Best of luck :king:
 

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when does the fuse blow?
on start? when you use a blinker (right/left)? or when something else is used? what else is part of that circuit.

you just need to start eliminating things.

also for purposes of doing the diagnostics, i'd suggest disconnecting the headlight. you may find that you'll have the bike key in the "on" position for a while without having the bike running to do some checking. at least that's how i like to do it. with the headlamp disconnected, you can work a lot longer without running the battery to dead.

i'll take a look at the wiring diagram a little later and see if i can give you some other ideas about where to check.

oh, and a good Digital Mulit Meter would be REAL helpful in this effort.

Alex
 

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Discussion Starter #8
Now we talking guys,

Let me try to recapture what happened.

I notice that after changing the fuse the blinkers (Left and right) seem to work fine at the moment. But then the fuse would blown up(same fuse-7.5) after a little while. Maybe because i ride it. But if, i was to replace the fuse and press the honk it would probably blown up immediately.

Stage 1:
This are the failures that i know of when the fuse blown. Blinkers not work, Honk not work, break light not work(but normal riding light are fine.) other than that to my knowledge it was working fine. I was still able to press the electric starter to star the bike and the display screen would be normal.

Stage 2:
Few weeks later, after changing 8 brand new fuses. Problem gotten worse, electric starter didn't work, display screen (odometer,speedometer) blank out, but was still able to push start the bike.

Stage 3:
Few days after that, i might have left the parking light on bike accident and came out of work hoping to be able to push start like other times. But everything completely blank. No more power. I keep tried to push start for 40minutes and accidently scratch the tank with my jacket while trying to jump on it. That was when i gave up. battery must had drain dry.

Going to use the battery tender to charge it. but, still have to find out the cause that keep blown the fuses up.

Yeah, sound kind of weird. Hope this recap make some sense. Sorry if didnt'.

Yes, i believed in let the pro work it. But i'm trying to learn how to fix and recognized my own bike. Beside, i would have to load the bike up on my truck and drive 2hours to San Francisco to drop it off to the nearest dealer. I'm in Sacramento.

This weekend i'm off on saturday and sunday. So i will be spending sometime looking and diagnos the electrical system.

hmmm.... i'm not sure if the workshop manual have it or not. but it wouldn't hurt me to ask for it anyway. I just DL the workshop manual from the site but haven't got time to read through until the weekend.
 

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there are 4 things (from what i can see) on the circuit fed by that 7.5 amp fuse.
1. turn signal flasher
2. horn switch
3. horn
4. rear stop switch

if i had a feeling about anyone of those going bad, i would check the rear stop switch first. it's in a rough location - under the bike, near the exhaust pipes, and it gets covered with dirt and oil.

the other thing i would suggest is to pull all the bulbs from the turn signal and tail lights, then replace them one at a time and see if one of those blows the fuse.

alex
 

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It sounds like your battery has had it. Trying to troubleshoot electrical problems with a bad battery is mind numbingly frustrating. I would suggest a new battery and keep it topped up during all the work breaks - like while you are sleeping.

Your old battery may be all or at least part of the problem.
 

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i would def listen to what drmasis has to say...i was having the same problem and have since stopped the problem. There is a group of wires within its own plastic coating that is near where the tank and rear section meet when closing the tail section down. Be sure that these are not being pinched.
 

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Discussion Starter #12
A lots of great leading.
Thank you all.

Will inspected this weekend. I am going to pay more attention from the rider seat to the back of the bike for damage or bad connection.

Will update when i actually touch the bike this weekend.
 

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Not to be redundant but...I had a similar problem. The wires beneath the tailsection that lead to the brake light can get pinched between the subframe and the bracket that holds the tail near the gas tank mount bolt. Check this out.
 

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Discussion Starter #14
Thank you for those that take part in helping me or respondng to my thread.

Bike is fix and happy to get it back on the road.

Thanks, much apprieciated.
 

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Discussion Starter #16
hehehe,

silly me.

It was because of my broken blinkers. there is a point of the wiring that maded contact with the bike. which caused the shortage.

Happy i got the bike back running and did it myself with out the dealer assistant. i'm just trying to have some personal growth.

The workshop manual really helpful.

Thank guys.
 

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Glad to hear you're back on the road!
 
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