Electrical meltdown! Don't even know where to start

Hello ppl,
I just had some vary strange electrical problems. First I took the bike for a ride and stopped for a bit. Then I started the bike and I noted that the tachometer was not working and the computer readout was not working. Then it turned on and off several times. I started to ride it and noted that every time I hit the brake the tack computer would loose power. I then looked at the break light and it was not working. I was running fine so I decided to take it home and only made it half way when the bike started to loose ignition. It would sputter for a sec and then recover and run for a min or two and then sputter. This happened about 4 times and then it quit all together. Then bike would not even try to turn over and I had to trailer it home.
The head light and tail works when I turn the key but that is it.

I will be digging into it and am not sure where to start.

Any help would be great.

 

Could be something in the fuse box. Is it original? If so maybe time to replace with a modern blade style fuse box.

 

Jamings67,
Can you please set up in your signature line what bike you have?
These 30 year old plus bikes are notorious for bad electrical connectors.
Remove your headlight and check every connector in there. You will find several of them turning black or green. The moisture from rain and morning dew gets in there and corrodes the cheap brass that the factory used in the connectors. If they are cleanable and you can salvage some of them use automotive dielectric tune up grease to seal them so the corrosion stays away. Worse case you will need to replace some connectors. Chacal xj4ever has what you need or if not keeping the connectors stock NAPA has some weather Pak connectors that work, but you will need the special crimper to crimp the terminals. I would advise to go through every connector on that bike just because of age and to try to eliminate any future problems. Let us know what you find and pictures are always nice to show what you found.

 

Fuses and/or regulator

But check your side stand plunger switch just in case it's a bit sticky and was juuuuust barely making contact to begin with but then ended up losing that due to vibration

 

Its a 1982 XJ1100

 

I have already replaced the fuse box with the blade style. I see now that several fuses have blown out. Must be a short somewhere. I will get back you guys as soon as I see a problem

 

If several fuses are blown, that's a goooood indicator of a failed regulator

 

I agree, I did replace a fuse and the bike started right up. I shut it of as soon as it stared encase the regulator is not working. I know that the tachometer runs off the regulator so it's been on my mind. The brake light cutting the power is a short I need to find. The wires for the rear lighting has been week and patched several times. I had a loss of ground last week and found a wire the was broke. There is BLUE wire hanging down from the pack and is not connected to anything and is live. ?? The guy that had the bike before me hacked the harness and installed different taillights so he could use saddlebags.
I replaced the main harness when I got the bike in 09. Over all the harness is in good shape and I use elec grease on the connecters. The main tail light power stopped supplying power from the main harness a while ago. I just ran a wire to the fuse. This might take awhile

 

Typically the rear tail light/brake light hot wire is blue..........

 

Yeah your correct, I think its time to remove the rear harness and replace the wires. Should be Fun!

 

Easy to test regulator-- start the bike up and put a bolt meter on the battery terminals... Should be around 13.5 +\-. Slowly roll on to the throttle.... Bolts should increase to 14.5 or so, then level off no matter what the rpms go to. If the rpms keep climbing over 15-ish, your regulator isn't regulating.....

 

Okay I will do that after I rewire the rear lights.

 

The fuse box is kind of a tough one because the space is real limited more so then the other bikes with the box under the seat. Yamaha got it right in there tight under the side cover. You could move that aux terminal and maybe fit the blade style fuse box in there. I have one bad fuse clip in mine and I am using an inline fuse holder till I figure out the best way to tackle that job.
Did your bike have the Vetter hard bags where the turn signals had to be relocated? My second 1100 has the butcher job on the rear signal harnesses that I need to address also.
If you get a chance snap a picture of your fuse box might help me see how yours fits.
Thanks

 

The fuse box has been updated a few years back. I have a post with photos somewhere ? Here take a look at this.
http://xjbikes.com/forums/threads/h...thout-moving-it-on-xj1100j.20890/#post-177212

 

Okay I removed the rear lighting harness and will replace with new wires. The problem I am having is tracing the main tail light power. Its a blue wire with a white stripe. I unwrapped the main harness as far as I can without removing it. but the wire looks good to that point. I am assuming the wire goes to the headlight bucket but I only see blue wires in there, one of witch is not connected to anything, there is some blue wires that go to the front blinkers that are connected correctly. I also have a brown wire that is not connected that comes from a two wire harness, the other wire is green with a yellow stripe. here is some pics IF YOU KNOW WHERE THEY CONNECT PLEASE LET ME KNOW! THANKS
solid blue wire in bucket not connected to anything

another one not connected ?
The blue wire with white stripe I need to get power from. For rear tail light

 

UPDATE
I unwrapped the harness a bit more and found out that the blue /white wire goes to a blue wire that has a burnable link. A link that is in a shield and made of a silver wire about an inch long. I will solder it. But I think this is the blue wire that is not connected in the headlight bucket.

 

The solid blue wire comes off the main (key) switch and it should have a 10A fuse (in the main fusebox) and this wire runs to the 2 "parking lights" and then to the computer. The blue/white tracer stripes exits the computer and runs to the tail lights. I don't recall any burnable links within these harnesses.

The only green/yellow tracer wire used with the front brake light switch (that plugs into the front master cylinder). It uses the brown wire for power.

 

okay I have working front parking or driving lights. I have a blue wire in the bucket that comes from the computer ans goes to the two front lights and then out to the main harness. This blue wire comes up from the main harness and has a double female connector. I cant find anything that goes to it. I found a double female connector from a brown wire and one was open so I plugged the front brake light into it. I have also found some connectors near the battery and volt reg that are unplugged and cant find any matching plugs. One is a two prong male in a white rectangle with red and black wires.
Two near the REG one that is a male two prong that has never been connected and another that is 4 or 5 pronged and looks like one that is next to it that goes to a relay. The black and red two prong one May have been connected and I might have just disconnected it while unwrapping the harness yesterday.

Thanks I hope I can get it fixed.

 

I cannot speak directly to the Xj1100, but many of the other models have unused connectors that are meant for use when a touring fairing is installed.

 

Oh I do remember seeing this here awhile back. I was concerned about the fuse box on its side with the blades up with water gettingbinnthere

 

I have a wire diagram for the 1100.
It's part of my XJ1100 owners manual
I can go to the library and lay it down on a big copier and send it to you if you need it.
Let me know

 

I just looked over the wire diagram and I don't see a fusible link anywhere. There is a diode in the clutch switch circuit but no links. If they put one in there it's not on the schematic for whatever reason

 

I have a manual, It helps but I am still confused, I had the bike s it would start. I made a good connection with the blue wire. plugged in the front break switch to the brown wire. I removed the rear lighting harness and reworked a 5 wire cable and connected it to the main harness. This cable is cut flush at the moment. I will get to it soon when I reinstall the rear lights. But I had the rear harness off yesterday and this bike started right up. Now there is no power with the key on at the fuse box. Everything looks okay I did unplug a few things when I unraveled the main harness from the back to about the gas tank mount. I also unplugged the wires that go to the starter solenoid. I plugged it all back in as far as I can tell and now no power from the key. Or to the key. I am getting frustrated. I just don't know electrical is not my thing.

 

Thanks I appreciate it but I have a service manual.

 

The blades are mounded into the box. Water won't be able to get to the fuses, and some dielectric grease on the outer connections will prevent any corrosion from forming.

 

OKAY I got the main power fixed and the wires to the tail light replaced and working. I have working rear blinker power wires but with no ground wires.
The question is where are the rear blinkers ground wires grounded? Do they have to go back to the black wire that the tail light is connected to? Can I just ground one of the two wires that come from the light? How is the connected with a stock setup? I see that the black wire that comes out of the rear harness has three places where you can connect to it. I would think that ground wire is for all three rear lights brake and turn signals. Do I need to run wires back to it or just to a grounding point or to the back of the brake light ground that id connected to the main harness black ground? I hope you guy know what I am saying. okay here are some pics of the harness I am installing. Remember that the red wire is the power from the blue wire in the harness. all other colors are the same as in the harness.
green and brown are power for blinkers

you can see that the ground wire is connected to the tail light here


This is the connections at the rear of the main harness. Note that there is are three connections to one ground wire.

The question is do I need to connect to this ground for the turn signals ? If so then Can I just make a connection at the brake light as it is closer to the blinkers and would save me the trouble of adding more wires, What so you think?

 

On the other XJs the signals are grounded through the harness. I suspect that the Yamaha electrical engineers did that for a good reason. There are not a lot of amps to work with and you really want as little voltage drop in each circuit as possible.

 

Okay that is good enough for me I will connect them to the ground wire.

 

Okay the wiring is done! Back to the problem. With the key on I get 12 v and everything works, lights and computer come on. It starts fine. When it is running the volts drop to 11 v at idle. When I rev it the volts drop fast and are consistent with rpm I shut it down when I saw that at abut 3k the volts dropped to 8v. So not what I expected. Do the coils draw that much power if it's not charging ? Could it be the regulator or should I look at the charging system? Let me know if you have a clue as to what the problem is. Thanks

 

The regulator is part of the charging system. Given that you see a big voltage drop as RPMs increase I think you need to check the alternator brushes and the copper slip ring on the alternator rotor. I think you will find that the alternator is not making electricity (or not making it go anywhere) and you are just running on the battery.

 

+1 what he ^ said.

Gary H.

 

I will be digging into it today and I will let you guys know what I find. Thanks

 

Okay found a problem with the connector from the stator. Three white wires. The connector to the Volt regulator is bad. It was not great when I installed it years ago. It got hot and melted the inside of the plug and now two of the tree wires are touching. The plug end that goes to the regulator has a blade that is twisted as little. How should I fix this? 1 cut off the connectors and install push in plugs? Two cut off connectors and solder the wires and then shrink wrap? 3 replace stator and plug it into a questionable Volt Reg plug most likely will work. I also need to know if the three white wires need to go into the reg in the same place as they are or can you just connect them in any order? let me know. I also remember soldering the three white wires in the harness as this website suggest some years ago.

 

Depends on the quality of repair that you are looking for.

You can rig it with local parts and likely have a reliable bike.

You could purchase used parts and replace

Or, I believe Len (Chacal) carries all the required parts to replace the connector shells and wire terminals. The biggest expense is the crimper, which I believe he offers for a rental. So, might want to contact him and get a quote for your needs - info@xj4ever.com

http://www.xj4ever.com/crimping my style.pdf

No particular order required.

 

Thanks I am going to replace the connector with push in style connectors. I might need to replace the Reg in the future and its cheap and easy.

 

Fixed the wires and have 13 v when running but the computer and tack do not work. What do I check next?

 

Did you inadvertently get rid of the splice when you repaired the AC Generator wires? One wire from the AC Generator goes to the Rect/Reg and the tachometer, another one goes from the AC Generator to the Rect/Reg and to the computer. The other one from the AC Generator goes directly to the Rect/Reg.

Does the CMS power up but not cycle through the status check?

Does it go a bit higher when you rev the motor to 2500 or so, with a voltage of at least 13.8.

 

I just cut the three white wires and reconnected them. I may have changed where they where but I was told it did not matter. The other two wire connector was good. The computer was turning on when I turned the key on yesterday but went out when running. Today it will not turn on with the key on and no change when running. I am using a analog tester and I see 13v at 1500 and up to about 3 k the tank is off so I only ran it for a minute.
So one of the white wires powers the tack and one white powers the computer? But they all are the same or just positive power correct.

 

So, this would make it seem that it failed yesterday before you repaired the stator wires today. Did you check the tail light fuse, which also powers the computer?

If Yamaha did not change anything, the white wire that goes to the computer from the stator is used to initiate the status check, and would not keep the computer from powering up.

Also, be sure to check the signal fuse for the tach not working. Do the brake lights work?

Which fuses were bad earlier?

 

OKAY took anther look. The fuse for the blinkers was blown and I replaced it. Might have blown when i ran it last night with the bad connector. The tack works now. The computer will not light until I press the start switch part way. Then the it reads all the displays. As soon as i let go or start the bike it goes out. There must be a bad connection with the computer power wire. were can I find it in the headlight? Tail light works good

 

Disconnect from the main harness and three phase ohm test the white wires coming from the stator. The reading should be the same for each phase.

Gary H.

 

Isn't this the 2nd time it has blown? Might need some more investigation as fuses usually blow for a reason. Did you try applying the front and rear brake to see if all is well?

The start switch on the right hand control to start the bike? Does the headlight come on when you turn the key on - it should. Yamaha doesn't give any detail on the computer, so headlight power could be part of the supply power. Although that would not make much sense as then it would be normal for the computer to blank out momentarily when starting the bike.

Are the parking lights on when the key is on?

 

okay , Gary I tested the white wires ohm and the book says .047 or something like that. The tester shows a good conductivity with all three wires.
Rooster, I think it blew when I ran the bike last night before fixing the shorted stater plug today. Yes the starter switch. All other lights work good now. Bike starts right up. I still don't know if it will blow fuses again until I run it more. Still not sure if its charging right. The books says 14.5 with higher rpm.
Getting 13 or so for the few sec i ran it. I guess I need to find the power to the computer at the headlight and test it. But what wire is it and in what connector?

 

One other thing , parking lights? When the key is on or the bike running the two front signals are on but the rear are not. The rear on my bike are red so it works fine but is this normal for other bikes?

 

Computer power problem found! The main computer harness connector was at fault. The white w red stripe wire was not making a connection because the plastic housing is deteriorated and not holding the male prong in place allowing it to move out of the connector. I just pushed it back in and held it when pushing in back together and it works. Just a little worried abut taking anywhere with it only charging at 13 v. Would you ?

 

OK, so I have two wiring diagrams for the XJ1100, one shows a blue wire going to the computer as direct power from the tail fuse and +12V from the signal fuse. The other diagram shows +12V from the signal fuse only. I think I trust the one with +12V only from the signal fuse. So, input power to the computer should be a brown (Br) wire and part of a six pin connector.



Just saw your post on the computer, good deal. I was going to suggest the brown wire as above. From what I can tell the W/R wire is the battery sensor?? But hey, if it works I'm not going to argue. The 1100 has way too many wires!!

Well you haven't checked it at higher RPM's. Need to do that and with 13V near idle I suspect it will be OK.

Running / parking lights for the XJ700 are annotated as front on the wiring diagram

 

Update..... I put it back together and ran it for a few min. Getting 13v running as far as I can tell from my tester. took it up to 5 k and held it for a bit. The fuse for the computer and tack blew. It was a10amp that I had. I put a 20 amp in and have not had it blow since. Tested the load by using high beam and turn signals and heated grips. No change in charge still 13 on my meter. Okay passed. I decided to take it for a ride and see how it dose. It went well and everything seems to work. One little thing that popped up as not normal is that the Neutral light will come on and stay on when running in all gears. The light works good and will go out when its on Key power only and in gear. ???? another thing to fix. Well it goes down the road now and a big thanks to the guys that helped!
I am including a video of some of the test drive! take a look

 

What I am hearing you say is that you like electrical fires. The only 20 amp fuse on your bike is for the main circuit; all others are 10 amp.
You need to find out why that 10 amp fuse is blowing and fix it!

And I think I may know the answer to that question.
At what point did you mention that the bike has heated grips?
From where do those grips get their power?
If it's from the circuit that is blowing fuses then the grips should be rewired to their own fused and switched circuit. You also should figure out how much current the grips draw so you don't end up with a flat battery. You only have so many amps to work with, and there isn't much left over for accessories. They may also explain why the alternator connector melted (too much load on the system).

 

Hopefully it went a bit higher than that at 2K and above, the actual spec is 14.5 +/- .3V.

The signal fuse on the XJ1100 is spec'd at 20 amps and does power the tach along with the brake lights, flashers, cancel unit, neutral light, warning light, and horns so should be OK.

Good questions on the heated grips, need to be sure they don't cause an issue.

That is a strange one. Would have to speculate that the vibration of the motor is causing issues with the switch??

 

OK. I'll have to go back and ammend the info I have for the XJ1100. It may be from an older version of Chacal's catalog.