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Discussion Starter #1
So our friend Daniel steals, er uh, buys, a non starting F4 1000. The fuse for the latch relay/power relay/instrument cluster keeps blowing. We've unplugged everything we can think of and the fuse blows. We bought a new diode and installed it thinking that might solve the problem. Still doesn't work.

Any ideas?
 

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Carl;
somebody posted about water getting into the main harness at the low spot behind #4, there are splices there and water kills them

I hate electrical shit
 

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Carl, there has to be a short to ground somewhere. What is the fuse number?
 

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Discussion Starter #7
We'll check the harness today. I thought about the ECU and every other electrical component. I unplugged the ecu and pulled it's fuse and still #15 blows.

Good thing we called Ed and he suggested we get a circuit breaker. Much cheaper than replacing fuses every time. A good thing to have in the tool box.
 

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So, fuse 15 immediately blows when you turn the key to ON? ACC? PARK?

...or when you hit the START button?
 

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Discussion Starter #9 (Edited)
fuse #7 counting from front to back. There are 8 total. I don't know if it's #7 in the electrical diagram.

Immediately when you turn the key, Chuck. No lights, no dash, no fuel pump. No sounds of relays clicking. We'll dig further into it today. I figured it was a direct short but I can't find it. The wire harness looks fine. No signs of water or wear anywhere. I'll look more closely today.
 

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I think you'll have to be cutting in to that harness. Check all the things that normally light up when the key is turned on. One of those is the tail light. Check under the metal strap that holds the tail light wiring under the seat. Sometimes the rubber sleeve that is there to prevent chafing has slipped and the wires there are shorted....it can be a very small indication.
 

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Carl, I'll do a harness check through the diagram here as time allows. Cindy and I are packing for a trip and we'll be out of the country for a week. (We are staying on the boat I help buy for my divorce lawyer for a week in Grenada!!) Don't worry, the house will be protected by a very angry gay troll with a Modified Mossberg. Plus, my daughter and her boyfriend will be staying here....lol.
 

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The fuse you speak of is a 15A fuse for the headlight main and dipped beam. Fuse B-2.
 

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Carl, is the bike with you or with Daniel?
 

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Looking at the wiring diagram, you want to trace the YELLOW wire from fuse B-2. This wire provides power to the lighting and dash and goes through all of the major components that make the bike run...such as the alternator and ECU. My bet would be that, where the harness takes a bend after the fuse box, there will be water and a ground or the solder connections are corroded. You will have to do surgery to find out.

Conversely, you can probably confirm that by taking the key to PARK instead of ON. In PARK there is only one circuit energized and this will eliminate things in the BROWN/BLACK wiring that are also energized when in ON.
 

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Discussion Starter #16
Both the bike and Daniel are here. I don't think it's the headlight fuse. The label on the fuse cover indicates it is the Latch Relay/Power Relay/Instrument cluster.
 

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The fuse you speak of is a 15A fuse for the headlight main and dipped beam. Fuse B-2.
But would that fuse blowing prevent anything other the headlight function?

Carl, unplug the handle bar swithes...

Actually, unplug everything from the entire harness, set the circuit breaker and then begin plugging things in. Obviously starting with the main switch.

Good luck. I'll call you if I get a chance.
 

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HI Ed....on the phone with Carl and Daniel...I had the wrong fuse...it was G-7.
Turns out there is a diode across the general relay that is bad.
 

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Discussion Starter #19
Chuck correctly diagnoses the problem:

Did ya'll know there are two diodes on these bikes? I didn't either. The diode that no one knows about was blown. Replaced it with a new one and the bike fired right up.

Daniel is one happy camper.
 

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Outstanding !!!!
 
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