Weird electrical- please help identify problem?

81 XJ750 SECA.

(Not what it looks like, I know, but I promise.)

End of last season I noticed the battery had died. Cleaning her up for spring, and here's what I'm getting:

Left signal is on, steady not blinking, all the time. Full off, key out, battery removed. (just kidding on that last one.)

Entire dash seems linked to signal switch. With the key off, if I turn on the right signal, the whole dash lights up, full accessory. Push signal to left, dash shuts off except left signal, which stays steady.

This is above my pay grade. I can track down a simple bad circuit, and I've even rebuilt a few ignition switches, but I honestly don't even know where to start.

Anybody else ever run into this craziness, or have an educated guess on where to begin? Should I tear down the ignition switch? Replace the signal switch? A perfunctory glance at the wires didn't show anything weird, but I didn't dig into the harness. If you think this is a crossed wire, any guess as to where that might be to get these symptoms?

It's got aftermarket LED signals. Can't imagine why that would matter, but there it is.

 

led lights could be the problem as the stock flasher will not work with leds unless you put load resistors in the circuit.
there is a thread on leds and having everything work.

Clean and lube the ignition switch

start with the ignition switch nothing should come on when key is off

 

The LEDs can cause wierd elecrtical backfeeds because they are also a diode, know a few people had issues with em effing up electrical if you bugger the polarity, pos neg, i stay away from em personally.

 

To add, a backwards led can esentially cause a backwards short, no ground, grounds to pos. Backfeeds idfk, i kept stock!

 

Key-off/key-out should result in no blinkers at all. Ingition switch may need replaced or cleaned/rebuilt.
It's also possible that a PO did some creative wiring.

LED signal lights won't cause any trouble if the correct relay is used, and the self-canceling feature can be retained when a two-relay setup is utilized.

How to convert to LED's and still have everything work

 

No it can't. The only issue with installing a LED lamp backwards is that it won't light up. You won't get backfeed, beause in the configuration the LED is acting like a switch that has been turned off.
I think you're talking about using one in a shared lamp system (like the single dash turn signal indicator on the 650), which relies on backfeed to function with the stock incandescent lamps. In that case you need to add steering diodes to prevent the backfeed so the indicator lamp will work and not cause all of the turn signals to come on at once.

 

any speedo with a shared blinker indicator needs a bidirectional diode LED as its ground is through the unused blinker bulb.
with the 2 indicator styles you have to make sure the led is in in the correct direction or use bi directional leds as that style the indicator bulb does have a true ground.

 

I was referencing what needs to be done when retaining the single incandescent dash bulb if you switch to LED indicators.

 

If you have the stock lights I would return it to OEM and then go one light at a time. By replacing one at a time and then see if the problem returns. If it does, you should be able to trouble shoot why the one LED light is making this issue happen. I think you will find that there is a shared power issue and the LED is causing the issue. As k-moe and others above have states, might have to do a little more modding if you want to add all LEDs. Good luck.

 

Is just the left indicator on or the actual signals too? Since the left blinker is on all the time, I would look into wiring for those if modified, otherwise start looking for a short between the left signal wires and positive. The bulb is getting power somewhere all the time, by turning the left blinker switch on with the ignition off you are feeding 12 back into the circuit which is causing the dash etc. to light back up. I would look at the LED flasher as well, although you would think you'd have the problem on both sides if there was an issue, be good to make sure it is wired in right.

 

Hmm, does this model have an electrical signal cancellor or mechanical? Sounds a lot like a relay + cancellor stuck state.

 

I got the bike with LEDs and it worked fine for two years, but I have a parts bike w/stock blinkers and will happily try this if it still seems like a good approach. (Replacing blinkers is solidly within my limited technical skills.)

You still think this is a good starting point even if the LEDs were previously working fine?

 

I believe both? The signal goes off after a period of time on its own, or you can poke the switch and it goes off. Is this what you’re referring to?

Any tips on where that potentially faulty relay might be located?

Thanks!

 

Electronic. If the self-cancel were the problem then the same condition would exist with tungsten bulbs (which is a good test of the self-canceler when any modifications are made).


OP,
The self-canceling unit is under the fuel tank and looks like a very long relay. Unplugging it removes it from the system and reverts it to a normal push-to-cancel system.

 

Will the bike crank with the key off in any of those conditions you posted in the video? If it won't crank then:

The flasher relay is normally accessible under the tank - the pic is the stock one but if you have and aftermarket it should be a similar 2 or 3 prong device connected to a black connector. The self cancelling unit is under the tank and can be disconnected and the flashers should still work.

 

If the stock flasher is still being used (likely since a lot of people just install resistors to load the system for LEDs. A sloppy solution IMO, but a popular one) the problem very well could be internal to the flasher. It is not a sealed unit, and corrosion can form causing the contacts to stick. The cover can be popped off and the contacts cleaned with a points file or emery board.

 

if led relay try to adjust the flash rate move adjuster full each way .

could be your led system is wired directly to battery.



voltage through the indicator bulb may be feeding the display
if you pull the signals fuse do you still get same results?
test for voltage on input side of signal fuse with key off and at the other fuses.

the main fuse is the only fuse that should have power with key off.

when you pull fuses it may isolate the issue to a circuit

also it may be time to remove the controller to check its wiring. relay feeds control then control switch directs power to signals

may want to unplug your battery level circuit at the battery

 

Thanks a lot for all the helpful responses!

Tore down and cleaned/polished both ignition and signal switches. Both seemed good.

Only power to main fuse with key off, all other fuses dead as they should be.

Replaced or disconnected all signals, so no LEDs currently plugged into bike.

Symptoms remain, even with auto cancel assembly and flasher relay disconnected.

Weird dash light flashing thing happeneing now, see video.

At this point does it have to be a hot wire making contact with a turn signal wire, or related?

 

that yellow wire goes to canceler unit. tape it off
that wire you poke is brown/white and is the power output side of your flasher relay did you resolder that wire
wires to relay with key off there should be no power to those wires color should be brown and brown/white

brown should be power input to relay wire

with key off check the wires voltage from key red is always hot brown is output to fuse box and should only have power when key is on.
blue wire goes to the tail lights/plate light should only have power when key is on.

if key is off and you get power to brown or blue wire your ignition switch is suspect


do you have your battery charger set to 6 amps?

 

I would start to take all the connections apart and clean them. See if there is a bad ground or power bleeding over that should not be. Guess broken wire or connector that might be the issue. You can use a jumper wire from the + bat side and start to test out each leg of the turn signals. - bat to the frame of the bike on a good clean ground point. The battery being supper low could be a issue as well. Get a good charge on that battery and then start to trouble shoot.

You don't see any damage to the wiring harness on the bike? Look around the tank and seat area to see if a wire got the insulation rubbed off it along the backbone of the bike frame?

Great vid to show us the issue. Lots of people will be helping, keep up the great work and posting.

 

Not for sure this is related but a better pic of the fuse box might yield some good advice. I can see it well enough with this screen shot form the video and see that it needs some work.

 

That looks like.....
...maybe the whole reason why there is power when the ignition switch is turned off.

 

he metered out his fuses and said they are working as they should with key on and key off

main hot all others no voltage with key off.

 

with flasher relay pulled you should have no power to directional switch brown wire.

 

your fuses look like the center 2 are shorter than outer 2

 

It might just be because it's a screen cap, but think I see a jumper where no jumper should be.
The blinkers should not function at all with the key off, and unless I read things wrong they are working with the key off.

 

Yellow wire is taped.

I didn't resolder anything, all the solder in the switch looked pretty good.

I had the charger on 2 amps. Plugged in a new battery today, all the same problems. (Though I did go for a long ride to renew my motivation for the project, so not time wasted.)

I'll check the power on the blue and brown wires from the ignition tomorrow and report back. I tore down and cleaned the ignition switch, and it all looked pretty simple, like if it was faulty it would be pretty obvious. I'll replace it if you more experienced folks think it's the culprit, but I just didn't see what could be going wrong with it?

 

18 months ago I had a short on the kickstand safety circuit that actually melted that wire. It resulted in me taking out & opening up the wiring harness to inspect the surrounding wires and make sure nothing else was damaged. It's possible I missed something, but I put liquid electrical tape on everything that was even slightly worn, and then rewrapped the whole harness. So it would surprise me a little to see wear, but God knows I've screwed up simpler things before, so I'll take a closer look at it tomorrow and see if anything shocking jumps out at me.

Could be damage to some other circuit though, I only rebuilt the wiring harness that housed the kickstand safety circuit. This is where I could use some guidance, because I really don't even know where I'm looking. I love this bike dearly, but compared to my old Honda CM it is basically made of wiring. (Only reason I know where the kickstand safety circuit is is because I followed the melted plastic.)

 

I'll post better pics tomorrow. That fuse "box" has been on my mind since I bought this rig, but to date, it's always seemed to do it's job just fine.

The two center fuses are shorter. In the aforementioned kickstand circuit short, they blew, and the replacements are the same spec but a little shorter. Does this matter? If they're the same spec, shouldn't they do the same thing?

 

So remember I have no clue what I'm doing. I'm assuming that little box that says "LED Flasher" is my flasher relay. Is this correct?

With that thing unplugged, the left turn signal indicator was still steady on. I didn't check the brown wire in the signal switch with the "LED Flasher" box unplugged, just looked to see if the light was still on.

On this note, is switching back to normal signals while leaving the "LED Flasher" relay in place going to be problematic? Kinda seems like I should scrap the LED specific relay and find a normal one?

 

Yes, that would be correct. It may have a rating stamped on it so in regards to keeping it with incandescent bulbs you would need to verify it is rated high enough for the two 27W bulbs if stock bulbs are installed. Switching back to a stock OEM will be a bit of a pain since the OEM connector has been removed.

What happens if you push the turn signal switch forward, which will create and open between all contacts? Does the left turn signal indicator go out? Jayrodoh asked earlier, but just to repeat the question as I don't see an answer - are the left flasher assemblies lighting as well as the left flasher indicator when the key is off?

With the turn signal switch pushed opening the contacts, check the rear left and right turn signal wires at the main harness with the test light or a meter if you have one. They should both be zero volts.

The shorter fuses reduce the contact area somewhat, but they are probably OK.

 

if you do have voltage at the brown white wire when every thing is flashing with relay out electricity is coming in some other way.
you do not see any extra wires hooked to the battery wire do you?
look at horn wire it is a live wire going to the controller.

does pulling signal fuse out stop the issue?

he is using a smaller blinker not an oem size bulb.

with flasher removed the power to the control must be coming from someplace else and the blinker switch is conducting the voltage

 

If you push the signal switch forward it changes whether the rest of the accessory setup has power. I tried to get it in the vid below.

Yes, both left signals also have power. Does this also support the theory that there’s power leaking into the signal switch from somewhere weird?

 

No hitchhikers on the battery or solonoid.

Didn’t check the main fuse, but pulling the others had no effect. I’ll check the main fuse later. It’s a good idea because if pulling the main doesn’t effect the problem, the short must be between the fuse box and the battery, right?

 

Here’s the fuse ‘box’ and the read outs on the ignition switch.

 

check out your voltage regulator
it is the only thing with power from battery not going through the ignition switch besides the red wire to ignition key

just unplug it
if you pull main fuse it will also kill power to Volt reg.

 

Disconnecting voltage regulator does not effect light. Removing main fuse does, everything goes dark.

 

May have found problem.

Disconnected red wire from fuse box to ignition harness. Used jumper to bridge same. No more constant signal light, everything goes dark when key is off, everything seems ok.

I know it’s not best practice, but is there any reason not to just add a new wire and leave the old, shorted one in there, taping both ends?

 

Hmmm, well that is one way to do it. Do you know why that worked? I mean was the fuse box melted from the previous damage from the side stand? At least you know know that once you fix the fuse box and change that old one out, you should be good to go. Most of us change that fuse box out just to stop problems that might turn up down the road due to broken or corrosion for the wires and connections.

 

this is good info

 

you need to improve your crimping skills.
as far as leaving the disconnected in place, just cut the exposed leads off of the ends of the wire and heat shrink the ends or tape them as a temporary fix only.

so let me see if I understand what you did.
you have removed the red wire from main fuse out put which goes to the Ignition key switch (red wire). replaced it with a new red wire from fuse to key switch and
by doing this all problems have gone away.

this is a good thing but also a bad thing. there may be wires melted/shorted into the red wire you disconnected. you will want to trace the bad wire through the harness at some point so you do not have a system failure down the road.

 

Totally agree here. I would add that motorcycles are dangerous, and anything that could potentially cause the bike to shut off is a real hazard to your safety - think busy fast moving freeway traffic and the bike suddenly stops running. I personally would inspect and repair the original harness and go with it if I felt good about the repair. That said, the proper repair would be quite a challenge when dealing with the original sleeving and you would need to invest the time and money to replace defective wires with properly crimped terminations.

Or find a nice replacement on Ebay. It may take some patience on Ebay as most of the harnesses that appear are hacked up and would be no better than what you have.

 

Ha! That's true, and in this instance I was trying to leave it pretty loose because I don't expect it to be permanent. Just testing the theory.

yes. I didn't thread it through the bike, just stuck a jumper on to see if it worked. Both blinkers currently turn on steady (not blinking), but I think that's to be expected because the rear blinkers are not attached to anything. Other than that, everything seems hunky-dory.

yeah, apparently! A quick glance at what's on there right now yielded some messy piles of shredded tape that I would defiantly not put on my bike. Better the devil you know.

:Sigh: I'll take it off and open it up. I'm sure you're right.

Hey, on a related note, my wiring harness behind the headlight feels super cramped. Like I can barely get it all to fit and then stuff the light in. It feels wrong. Is this just me? It feels likely that it's bending wires or stressing the little plastic parts. Is it a terrible idea to leave some of the harnesses outside the lamp assembly and just tape them up really well? How do you guys get those wires to feel tidy?

 

Yamaha left just enough room to stuff all the wires in. Don't leave any of them hanging outisde of the bucket. They are divided into two sections that lay on either side of the headlight, but it can take some time to get everything to lay into place. There are tabs on the horn mounts that are for holding the wires in place on their respective sides.


Borrowed pic.

 

ah HA! My headlight housing is round. Must not be stock. No wonder it feels to damn tight.

 

when you make the permenant install just run it along current harness where it wont chafe and tape/wiretie it in place.

as far as your blinkers should work when you hook up rear. with them disconnected bike thinks bulb is broken. it will depend on the bulbs and flasher relay you use.

factory flasher wants to see 2 bulbs at 27 watts.

if the little black blinker is what you are running is an incadessant bulb it is not going to be 27 watts

 

Tore down whole wiring harness, as recommended. Glad I did, there was a short in there with several bare wires. Spliced new wire in, replaced the wire from the fuse box to the ignition, patched everything up. (I know splices aren’t the best solution, but I don’t have all the appropriate color wire on hand, and whatever.)

Signals work, but don’t blink. Will get all bulbs to spec and expect that will be resolved. (Thx xj550h. If you hadn’t warned me, I’d be annoyed with the blinkers right now.)

New problem though- headlight not working. Getting just over 4v on the right hand (yellow w/ green stripe) wire. Bulb looks perfect. Is that voltage normal? Thoughts?

 

you have a head light relay and head light does not come on until motor spins and activates the headlight relay.

when relay closes
you should see 12 volts you have a high beam wire and low beam wire as switch is moved.

hi lo switch sends the voltage to hi or low and the light shuts off between the flip.

check that you have a diode block in the head light if you look ay K moes photo it is the black flat package in upper right corner.

 

Well now I feel like an idiot.

I’ll start it up when I get home and see if the headlight works. I do have a diode block. Had wondered what that was, as it just has wires going to it and not from it.

 

diode block some wires are input some are out put. see the diode on the White wires going to relay? that diode is in the block


white wire from alternator goes to block then another white wire runs from block to headlight relay.

wires on block may not match wire color in the harness connector