Turn & Hazard fuse failure

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
... Chocolate for left and Dark green for right. (OK, he said green, I said dark green. Fine. Dark grey is not Chocolate, though. He must be color blind
smile.png
) ....
You are quite right, I read "Ch" as "Charcoal" not "Chocolate". Not colour blind, stupid
sad.png
.

Colours corrected in the diagram.

 
Last edited by a moderator:
I replaced the flasher but it made no difference {didn't really expect it to}. The tank and seat are off. I disconnected the harness to the taillights {behind the air cleaner cover, left side}. No difference. Haven't found any exposed wires. Might have to remove front cowling for a thorough look.

 
Logically, the ground short must be on the "load" side of the fuse. But I have seen faulty metallic fuse holders where the insulation between the fuse holder and the chassis ground had disappeared over time. The ground fault just happened to be in the right place where it blew fuses immediately.

 
Logically, the ground short must be on the "load" side of the fuse. But I have seen faulty metallic fuse holders where the insulation between the fuse holder and the chassis ground had disappeared over time. The ground fault just happened to be in the right place where it blew fuses immediately.
Can't be the fuse holder, doesn't blow until one of the switches is activated.

 
True. I'm a fair enough wrench but not so good with electrics. I'll remove the front cowling today and poke around in there like I know what I'm looking for. Stand by...

 
Burned spiders would have nothing to do with fuses. Fuses blow when circuits are shorted to ground. Ground wires are SUPPOSED to be grounded.
You've got to find those two wires, chocolate and dark green, and follow them. It HAS to be on one of those wires.

 
And by "on one" I mean it's probably on both, since either direction blows the fuse. Which also means they're probably cut and shorted to ground somewhere together.

 
I bridged the turn signal fuse slot with a paper clip and measured DC volts at the turn signal and relay connections. The reading is 11.89 volts at all connections when either the hazard or turn signal switches are operated with the ignition switch on. Is this of significance? How do I go about tracing the chocolate/dark green wires to find the short? Must I cut the harness wrap in order to get a visual inspection? Could I use a continuity light? I see no grounded or cut wires so far. Stupid is as stupid does here.

 
I bridged the turn signal fuse slot with a paper clip and measured DC volts at the turn signal and relay connections. The reading is 11.89 volts at all connections when either the hazard or turn signal switches are operated with the ignition switch on. Is this of significance? How do I go about tracing the chocolate/dark green wires to find the short? Must I cut the harness wrap in order to get a visual inspection? Could I use a continuity light? I see no grounded or cut wires so far. Stupid is as stupid does here.
Not sure how you did your testing so it's hard to say if it is significant. Troubleshooting electrical can be very difficult. My recommendation would be to pull all of the connectors apart after the turn signal switch. Put a fuse in the circuit and operate the switch. If it does not blow you are good to that connector. If it blows the problem is between the fuse and connector. Next plug the connector in that goes to the load side of the switch. Operate the switch. If it blows the fuse the problem is in that section of the wiring harness. Continue this process unti you plow the fuse. It is critical that you start next to the switch and work by connecting one section at a time and the new section connects to a section that has been tested. Good luck.

 
I bridged the turn signal fuse slot with a paper clip and measured DC volts at the turn signal and relay connections. The reading is 11.89 volts at all connections when either the hazard or turn signal switches are operated with the ignition switch on. Is this of significance? How do I go about tracing the chocolate/dark green wires to find the short? Must I cut the harness wrap in order to get a visual inspection? Could I use a continuity light? I see no grounded or cut wires so far. Stupid is as stupid does here.
Not sure how you did your testing so it's hard to say if it is significant. Troubleshooting electrical can be very difficult. My recommendation would be to pull all of the connectors apart after the turn signal switch. Put a fuse in the circuit and operate the switch. If it does not blow you are good to that connector. If it blows the problem is between the fuse and connector. Next plug the connector in that goes to the load side of the switch. Operate the switch. If it blows the fuse the problem is in that section of the wiring harness. Continue this process unti you plow the fuse. It is critical that you start next to the switch and work by connecting one section at a time and the new section connects to a section that has been tested. Good luck.
Also need to think about the hazard light switch!....................

 
Going back to the original symptom, the fuse blows with either the hazard light or with either turn signal. The same fuse also supplies voltage to the taillights, front running lights, and the tag lamp, so it's conceivable (but not likely) that something's wrong there and adding a turn signal simply goes over the current allowed by the fuse. Depends on what's added to the bike that taps into that circuit for juice.

Suppose you added a radio, intercom, or something, that used, say 7 amps, tapped to the running-light wire (which is common) but without a relay (which should not be done.) The tail-lights, running lights, and tag lamp might together need 4 or 5 amps total. (Pulling these numbers out of my ass just to illustrate.) So far no problem. But then you hit a turn signal which needs maybe 6 or 7 amps. You might now be at 18 or 19 amps, a few over the 15-amp fuse. Without the auxiliary load of 7 amps, nothing's wrong with anything and the hazards and turn signal work OK. Pure speculation, just illustrating that an unexpected auxiliary load of some kind could put the circuit over, and do so only when the extra load of the turn or hazard signals are used.

The only way to know that for sure is to see how much current goes through that fuse without the turn signals or hazard lights. If that's more than half the fuse rating then it's not actually the turn signals that are the problem.

I find that unlikely, though. I think you've stated that nothing extra is tapped into the light wiring anywhere. So, continuing:

It is a Very Bad Idea to substitute a paper clip for a fuse for troubleshooting. By doing so you remove whatever protection the circuits have against carrying more current than the wiring can tolerate. If there is a dead short somewhere, by bypassing the fuse and activating the circuit you are allowing whatever amount of current the battery can supply into those itty-bitty wires running the length of your bike, and they will get VERY hot, melt the insulation, the insulation of wires adjacent to them in the harness, and create about 30 more problems that you didn't have before.

DO NOT EVER BYPASS A FUSE!!!!!!!! FOR ANY REASON!!!! EVER!!!!!

Having voltage at the end of the circuit is meaningless. You have no idea how many amps were being pumped into the wire. A dead short is still 12 volts off of a 12 volt battery, more or less. The fact that you saw 11.89 volts implies a pretty significant drop somewhere along the line, which basically we already knew.

The connector method is a good idea, but that assumes you know where the connectors are.

As for finding the wires, look at the connectors at the switches, see which harness they go in to. Follow the branches of the harness and look at the connectors they come off of. You should be able to see the connectors that carry wires of those colors, and thus map the path they take through the bike. That will tell you which connectors to unplug for Silver Ranger's test, and should give you an idea of what part of the harness carries the wires so you can look for defects, cuts, abrasions, and piercings in the harness's housing.

 
Last edited by a moderator:
Once again, thanks for the advice. I used a paper clip just long enough to instantaneously try the hazard or turn signal switch, then immediately turn the ignition off. Admittedly a bad idea. Thanks for the reminder. I won't repeat it. I have no extra farkles except for highway blaster horns and a power commander and both have been installed for years. No recent changes or additions of any kind. I disassembled the hazard switch today and all appears normal. I will continue with the trace and disconnect method and update my progress. This is a LOT more complicated than fixing electrical issues on my old 60s Brit bikes!

 
I followed the harnesses from both switches and unplugged the downstream connectors they led to, one at a time. They are located in a batch of wiring by the storage box and S6 spider. I tried the switches and the fuse did not blow. Plugged the connectors back together, one at a time, and the problem reappeared with each switch reconnected. This must mean the short is downstream of the connectors. Am I getting the hang of this? LOL.

 
I followed the harnesses from both switches and unplugged the downstream connectors they led to, one at a time. They are located in a batch of wiring by the storage box and S6 spider. I tried the switches and the fuse did not blow. Plugged the connectors back together, one at a time, and the problem reappeared with each switch reconnected. This must mean the short is downstream of the connectors. Am I getting the hang of this? LOL.
Those two connectors will be from the individual switches, so your test makes sense.

There are other connectors to try. There are two going one each to the front indicators, it's unlikely these will do anything since they are not common to both sides. There is a connector going to the meter unit that has common wiring, there's a connector for the tail lights. There's also one somewhere with six wires, colours:

  • Chocolate
  • Dark green
  • Black
  • Black/White
  • Blue/Green
Sorry, I can't tell you where it is.

 
I followed the harnesses from both switches and unplugged the downstream connectors they led to, one at a time. They are located in a batch of wiring by the storage box and S6 spider. I tried the switches and the fuse did not blow. Plugged the connectors back together, one at a time, and the problem reappeared with each switch reconnected. This must mean the short is downstream of the connectors. Am I getting the hang of this? LOL.
Those two connectors will be from the individual switches, so your test makes sense.

There are other connectors to try. There are two going one each to the front indicators, it's unlikely these will do anything since they are not common to both sides. There is a connector going to the meter unit that has common wiring, there's a connector for the tail lights. There's also one somewhere with six wires, colours:

  • Chocolate
  • Dark green
  • Black
  • Black/White
  • Blue/Green
Sorry, I can't tell you where it is.

On a Gen2 bike it should be just above the air filter intake......

Oops think i may have jumped in with both feet here. I got confused between the tail light connector and the other one you were referring to. The tail light one is just above the air filter intake.........

 
Last edited by a moderator:
Top