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Discussion Starter #1
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
 

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Discussion Starter #3
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
 

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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.
 

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Thanks, is it possible I just need a new battery?
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.
 

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Discussion Starter #7
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
 

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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.
 

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Discussion Starter #9
This was my first post but I’ve skimmed through stuff on here before. Pretty amazing response times. Thank you I’ll check some stuff out
 

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Discussion Starter #10 (Edited)
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
 

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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).
 

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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.

Very curious to hear the outcome of this.
 

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Discussion Starter #14
Thank you for the detailed response. I really appreciate it. I’m out of town and will be tackling your suggestions sometime next week.
 

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Discussion Starter #15
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
 

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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.
 

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Discussion Starter #17
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
 

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"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.
 

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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
 

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Discussion Starter #20
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.
 
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