Hi, I have a 2003 and I’ve been loving every second of it until recently. My headlight stopped working. I did the blue wire mod and the light works! Great except now it won’t start. I’ve charged it and then it starts but it needs another charge again or it will strand me. So I switched it back to the original spot for the wire and it doesn’t drain the battery but now I’m back to where I started with no headlight. Was there something I missed with the mod? Thanks
I’m sorry I’m not sure what you mean exactly. When I rev it it goes up to 11.5 then goes down. I know that’s much lower than it should. But it’s showing the meter go up but not staying anywhere substantial (with blue wire mod). Not sure if this answers your question. Thank you
One of the three wires from the stator acts as a trigger for the headlight relay, so if that wire isn't getting voltage, you have no headlight (unless you do the blue-wire mod). Or your relay has burned out.
Doing the blue-wire mod doesn't really re-route the circuit so that it uses any NEW components that might be causing a vampiric drain. It's more likely that your stator and battery are limping along just barely keeping you on the road when your headlight is off, but when the headlight is on, you're drawing more amps than you're producing, and you eventually run out of pixies.
11.5 is more than "lower than it should". It's "failing horribly".
I recommend you yank the 10-pin connector out of the junction box, remove the yellow wire, then plug the connector back in. Start the bike and check for AC voltage between the yellow wire and the bike frame. Don't let that wire touch anything while the bike is running! If you don't read something like 5v AC (don't know the "good" range) there at idle, your stator is fried.
Very unlikely. The battery mostly has an effect on starting. For the purposes of this conversation, the bike should run on it's own without the battery once the engine was running.
It never dies once running ever. It just won’t start after a couple times since the mod and will start everytime when I reverse the mod to stock. But no headlight
Hopefully the recommendations in comment 4 will shed some more light on the situation. While digging around in the wiring, it's probably worth checking the output of each stator lead, and checking for a short-to-ground.
For a week I was just riding in the day with the headlight off and the blue wire mod back to stock so the light doesn’t work and it fired up perfect everytime. Now, I redid the blue wire mod so I have a light and unhooking the 10pin box whenever I stop or overnight. Plug it back in and it’s started everytime. Somehow it must be drawing off the battery with it hooked in(connected)and not when it’s unhooked (disconnected). Do I just need to add a switch to make this function less of a pain in the ass? Why is the blue wire mod drawing power when it’s off? Thanks
Time out. Your battery doesn't drain when you remove the *10* pin connector? The blue mod should have been done exclusively on the 8 pin connector. If you meant '8 pin connector', then I'll dig deeper into that portion of the wiring to see what could be wrong (it looks bulletproof with a cursory glance).
Weird. There's nothing in the circuit that would cause a vampiric draw triggered by moving that wire. The voltage for the headlight is cut completely off by the ignition switch.
Your headlight is now protected by the "tail light fuse" instead of the "headlight fuse". I'd pull the tail fuse and use a multimeter to check for voltage to the battery on both terminals in the fuse block with the ignition 'off'. There shouldn't be any. Alternately you could check the amperage draw between the terminals with the ignition 'off' again, there shouldn't be any.
Just to be safe, do the same check on the headlight fuse. There shouldn't be any voltage or current there either with the ignition off. That fuse can be completely removed after the blue wire mod, so if you get any readings there, yank the fuse and your problem will be solved.
The only other thing I can see that could possibly be drawing power with the ignition off that would be affected by unplugging the 8-pin connector would be the R/R. If all else fails, try leaving the 8-pin junction box plugged in and unplugging the rectifier between rides to see if that solves the drain or not. That would be an odd failure, but I don't see any other alternatives.
UPDATE. I was getting around a 12.5 reading on the battery just sitting there. Started up. Kept testing it. Drops a bit lower after it starts the. Revving it will get it to 12.6 12.7 but never saw 13... Turned it off and the battery went down to 12.25. Rode it it again turned it off battery was at 12.35. Then I tested the battery with it off and it was around 12.3 to 12.45 and this time it wouldn’t start at all. Acted like the battery was completely dead. A lifeless attempt then basically nothing but clicking. One thing to note is this is all with the blue wire mod intact and the headlight on. Another thing I tested is you said I could remove the headlight fuse since post mod the light is on via the tail light fuse. That wasn’t the case. With the headlight fuse pulled I had no headlight. The blue wire mod was done the way explained because it does go on now with the key turned to ON. Even though the battery shows it at about 12.4 now it won’t start but I know it will start once I charge it up. And it started multiple times with a 12.25-12.3 reading. What gives?! THANKS
When you say “revving it” how fast are you revving? My bike will jump over 13v with just a little choke, only at warmed up idle (about 1k rpm) will it not charge. My key off voltage is 12.8, so besides the mod, have you tested your charging system? That’ll surely lead to the bike not starting. You shouldn’t have to charge it all the time just to start it up. Not sure what type of battery you have but fir an AGM, 12.5 is about 70% of full capacity give or take.
I was revving it at high rpms and low and it never got to 13. So yeah it must be the charging system. It just seems odd that I never had this issue until fixing the light by doing the blue wire mod. What’s the best way to check the charging system? Do you think I’m gonna need a new stator or rectifier or? Thanks
I would review the wiring connections like Thorn stated above but to verify the stator and R/R, on the left side of the motor you’ll see the black wire covers coming out, they are fished under the bevel gear and go towards the battery case under the seat, there’s 3 yellow wires that have bullet connectors on them, you can disconnect them there (doesn’t matter which way you reconnect them because they’re all the same), take a voltmeter and test for infinite resistance between each of the leads and the bike, one lead on the yellow wire, and the other either on the negative battery terminal or a bolt on the engine block. Point being is you should not have continuity, if you do the stator is shorted, if that tests good then test the resistance reading between any two of the yellow leads, I believe it should be .6ohms, the measurements are in the manual. If that all checks out good there are similar tests for the R/R
"With the headlight fuse pulled I had no headlight."
Whaaaat? *laugh* I literally today had to pull my tail light fuse in order to shut off my headlight! There's something totally screwy with your wiring. Could you post a picture or five of the wires going into your junction box connectors? Probably just easier for you to use the wiring diagram to verify that all the wires are the expected ones. I wonder if a previous owner did some splicing that worked fine until the blue wire mod was done.
Did you check for voltage/current when the ignition was 'off'?
And here's a crazy question since the headlight fuse is still in series with the headlight after the blue wire mod: Does the headlight go off with the headlight fuse in but the tail light fuse pulled? Wondering if somehow everything got daisy chained together.
It does not go off with the tail light fuse pulled and the headlight fuse in. Just when the headlight fuse is pulled. The wiring diagram shows 17 wires going into the junction box so I guess that’s including other boxes? I’ll send some pics ASAP.
I was getting around a 12.5 reading on the battery just sitting there. Started up. Kept testing it. Drops a bit lower after it starts the. Revving it will get it to 12.6 12.7 but never saw 13... Turned it off and the battery went down to 12.25. Rode it it again turned it off battery was at 12.35.
Is there anything wrong with getting an $80 jumper charger so I don’t get stranded and can stop having this mess up my summer any longer? I know it’s putting a bandaid on the problem but it would save me a lot of time and stress right?
Doing that will just cost you more time and stress. The bike is going to die at the worst times, and by the time you get it started and the jumper put away, it will be ready to die again.
Best short term patch would be to run a jumper from the positive battery terminal to a 10amp fuse to a switch to the input of the RLU.
I recommend a jump pack to everyone, but like Spockster said, if your bike drains down low enough that it won't spark, jumping it might get you another 2 miles down the road, but it'll be dead again almost immediately.
I left my lights on like an idiot, and drained the battery to zero. Managed to get it jumped with a jump pack, and rode for about 7 miles with no problem, keeping the RPMs high to put charge on the battery. Ended up hitting some traffic and thought I had enough juice built up by then to let the engine idle at a stop light. I was wrong. Bike used up what little charge it had (wasn't charging at idle RPMs), and died just as the light turned green. Waddled across several lanes of angry traffic and tried to push start it on the sidewalk. No dice. Jump pack that I was going to recharge at work was totally drained and couldn't help any more.
That'd be the razor edge you would walk every day until you get your stator fixed. Could die at any time, and once it dies, it's going to keep dying.
Killing the headlight might reduce the current consumption enough that you could make it home with what would normally be too little stator output.
When my stator finally gave in I was about 15 or so miles from home. I too died in traffic, I tried my jump starter but it wouldn’t work with an already severely drained battery. I ended up getting a jump from a guy in a truck which gave me enough juice to get close to home, it was highway riding until the last two miles and as soon as the rpms came down the bike sputtered out. Another guy pulled over jumped it one more time and I got home. This isn’t something you want to deal with. Everyone should have a jump starter but for emergencies, not daily riding. Every time the battery drains way low it’ll be a little weaker when recharged. Run the tests on the charging system and hope it’s the R/R instead of the stator. It’s an easier fix
Here are some pics I took of the wiring going into the boxes. My friend who has a shop is just really backed up so I went to this shop thats actually 2 doors down from me but they have a lot of harley stuff going on... anyways, I talked to the guy today and he basically said he will put on a new stator and R/R for $450. And have it done in a day! I'm thinking that's my best bet at this point. What do you guys think? I really appreciate all the help from you guys on here. Please let me know how that wiring seems to add up. Thank you
Well, the pictures solved one mystery, but not an important one. The blue wire mod was not done correctly, but in my opinion it has been done better! With your current setup, your tail light and dash are controlled by your tail fuse, and your headlight is controlled by your headlight fuse. (normal blue wire mod leaves the headlight controlled by the tail fuse, and the tail/dash is only protected by the main 30 amp fuse, and the headlight fuse is unused).
Unfortunately, all of those things have no power when the ignition is off, so there's no chance of a vampiric drain BECAUSE of the wire swap.
You said the drain goes away when the 8-pin connector is pulled from the box. The ONLY thing not completely de-energized on that plug when the ignition is off is the R/R. I bet if you unplug your R/R next time you stop, your drain will be gone. If so, time for a new R/R for sure, and hopefully your stator is still ok? Best to check the AC voltages on the yellow wires just to be sure.
Chances are that one of your stator windings is shot (probably the winding that used to turn your headlight on). $400 is a great deal if the mechanic understands that they're splitting the case. Otherwise your $400 might quickly balloon into something much bigger.
I’m thinking he may not realize the engine needs to come out or be tilted to get to the stator. The OEM stator is + gasket cost me about $440 alone. Plus the cost of 7 hrs of labor. And that was a Kawasaki dealership with so called “trained” mechanics.
Or, maybe your guy is just really good
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Kawasaki VN750 Forum
411.9K posts
42.1K members
Since 2000
A forum community dedicated to Kawasaki Vulcan 750 motorcycle owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, reviews, and more!