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Won't start; no headlight, no starter

20976 Views 24 Replies 10 Participants Last post by  Hans&Feet
Hi all,

Current situation
Fully charged battery; Engine stop switch in Run position; Tranny in Neutral; turn ignition on; neutral indicator, temperature dummy light, oil pressure light, running lights (front light bar) all turn on; headlight does not turn on, starter does not activate when I press the starter switch.

Background
I had been experiencing symptoms of lean mixture for a short while, and finally got around to cleaning the jets in my carb. I put it all back together and got it running, pulling it out of the garage and up the driveway. I needed to go get my helmet to take it for a test ride and turned off the bike. When I returned to the bike minutes later, it would not start (see Current Situation above).

I had been experiencing issues with my starter switch being "finicky" (had to depress it just right to get it the bike to start), but never had issues with the headlight not working. I had cleaned the contacts on the switch once before.

The only thing that was different from the hundreds of times I had started and shut the bike off before was, this time, I opted to stop the engine by turning the ignition switch off instead of using the engine stop switch first.

What I have tried

Knowing that there are two paths for switch settings to start the bike (Stop Switch in Run and either tranny in neutral OR kick stand up and Clutch disengaged), I tried all combinations of stop switch, neutral, kick stand switch, and clutch switch. Made no difference, so out come the tools.

Switch tests

- Neutral switch as continuity to ground when in neutral, no continuity otherwise (makes sense, seeing that the neutral indicator on the speedo works)
- Kickstand switch has continuity to ground when kickstand is "up" and no continuity when "down"
- Clutch switch has continuity when clutch is disengaged (i.e. when I am squeezing the clutch handle), no continuity otherwise
- Diode (flux capacitor? :lol:) has continuity in one direction only (negative lead on center pin, positive lead on each outer pin)
- Ignition switch has continuity between all posts when switch is "on", no continuity between posts when switch is "off"
- Jumping the two primary connectors on the starter relay causes the starter to turn the engine

Fuses
- The main 30 amp fuse and all 10/5 amp fuses in the fuse block are all good (pulled each one out and checked continuity/resistance)

Voltage
I'll skip the "where I have voltage" conversation as some of it is obvious based on speedo lights working...
- No voltage on Y/R wire at starter relay switch when starter switch is depressed
- Obviously no voltage at the headlight (seeing that it doesn't turn on)

My thoughts
- Bad Engine stop switch / Starter switch, since the electrical path for both the headlight and starter go through the starter switch, and that is goverened by the engine stop switch.

Thoughts?

I pulled the housing for the engine stop switch and starter switch apart, but cannot figure out how to disengage the throttle cables in order to get the stop switch out of the housing.

I definitely have voltage drop across the poles of the starter switch. I am going to get that cleaned up and lubed today.

If this engine stop switch / starter switch isn't the issue, I am thinking I need to start tearing into the wiring harness for shorts. I hate to do that since the bike was running fine until I turned it off with the ignition switch instead of stopping the engine with the engine stop switch first.

Any thoughts are welcome / appreciated!
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no headlight and no start. the starter switch is bad. the switched needs to be removed and cleaned and also the guides for the shunt need to be fixed. the overheating of the switch melts the plastic guides and prevents the shunt from sliding up and down. it sticks in the down position and stops the headlight ans starter from working. when you get the switch working again you should put your headlight on a relay to remove the power draw through the switch.

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One throttle cable has slack adjuster - simply create slack at this point - and cables will be able to pull out of throttle slide.

I'm sure you will find the starter switch is the problem.
Plenty of topics on it.
Do Google search - adding VTXOA to the end of term will bring you back in here to the site.
the overheating of the switch melts the plastic guides and prevents the shunt from sliding up and down. it sticks in the down position and stops the headlight ans starter from working.
That was it :thumbup:. The plastic guide is melted so badly that I am going to buy a new assembly and put the relay on with it.

I was able to rig the shunt enough to prove that the switch was the problem, and was able to start the bike. The headlight turned on, but after starting the bike, the headlight failed to turn back on. I was able to stop and start a few times, but the headlight never turned back on. So, safest route: new switch + relay.


One throttle cable has slack adjuster - simply create slack at this point - and cables will be able to pull out of throttle slide.
Thanks for this. Can't believe I didn't see it :oops:; I saw that the cable end had the "barrel and notch" setup but feared I would have to disconnect the other end from the carb. Guess I was so focused on the carb from attending to the lean behaviours...
you can remove the shunt and spring and use a 1/16 drill bit to hone the guides. this got me by for a long time
If that switch is burnt then you absolutely have something wired wrong.
if you have accessory highway lights or something that draws a lot of power (radio) connected to the wires in the headlight bucket that is why it burnt up. Do not connect any accessories to the bike wiring . All accessories should have a seperate wire running from the battery threw a relay.
If you just replace the switch it will burn up again.

Donut
If you just replace the switch it will burn up again.Donut
Thanks! I was going to replace the switch AND put the headlight on a relay. When I bought the bike, the previous owner had put a light bar on it; I'll be looking into how he wired them...
If that switch is burnt then you absolutely have something wired wrong.
if you have accessory highway lights or something that draws a lot of power (radio) connected to the wires in the headlight bucket that is why it burnt up. Do not connect any accessories to the bike wiring . All accessories should have a seperate wire running from the battery threw a relay.
If you just replace the switch it will burn up again.

Donut

the switch issue isnt just people adding stuff. i dont have any extras and mine melted
If that switch is burnt then you absolutely have something wired wrong...

All accessories should have a seperate wire running from the battery threw a relay.
Donut
Those statements are just wrong. Blanket statements like that usually are. THE ONLY thing going thru the switch is the headlight power line, so unless you wire into the headlight power any other wires in the bucket are not going to affect the switch operation. Nothing else goes out other than the headlight when you hit the switch so therefore nothing else is going thru the switch. Just look at the electrical diagram its only the headlight power. In addition, the headlight power line is fused at 10A, I don't know of anyone that adds directly to the headlight line and also ups the fuse to compensate for the addition. That switch is on a 10A fused line so by safety design standards the switch would be required to handle at least 10A.

The issue is cycles. Everything electro/mechanical has a life cycle. Everyone knows when you throw a switch you get a little arc, a light switch at home, an electric drill, just disconnect the battery in the dark and touch the terminal with the cable and even the odo holding current will give a little snap. You do this enough times at several amps and the surface of the connection erodes away, continuing the surface erosion you end up with a smaller conduction path, at some point the surface area can't handle the current and now you have excess heat caused by the resistance, current trying to conduct thru too small of an available path.

Regarding the relays, not everything requires a relay which is why many electrical accessories don't have them. It all comes down to what end function you desire and then design it soundly to meet that function. Other than the engine electrical requirements everything else is considered an electrical accessory on a vehicle. For example our horn works absolutely perfectly without a relay, but a lot of vehicles have a horn relay, put a stebel on an x and it is a good idea to do it through the relay. Why doesn't our horn have a relay? because the horn switch is adequate to handle the current of our little squeaker so a relay is not required. Stebel startup current is pretty high so you don't want to run it thru the stock switch.

I could give a lot of examples where a relay is desirable and where it isn't. For simplicity a relay is a switch and in automotive uses its primary purpose is to act as a switch, either as the main switch or to protect (bypass) a smaller switch. If you don't want/need it switched or the existing switch is adequate in size then a relay is not needed.

A CB radio for example. I wouldn't want that switched through a relay because I want to be able to still use it if I'm broke down on the side of the road without turning the key on. And it doesn't need another switch since it already has its own correct rated switch built in. Similar with my accessory power port, I don't want it switched because I plug the tender in there, I've used it a few times with my air compressor for flats, and I run my computer through an inverter off it when I'm in the tent. It is direct fused to battery.
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the switch issue isnt just people adding stuff. i dont have any extras and mine melted
Greg, thats surprising to here. All of the ones I have delt with in the past have been caused because of the accessories connected to the wiring in the healight bucket. There is not that much current going threw that circuit to burn up the switch unless there is a short omewhere. I'm guessing. So that really puzzles me.
Anyway the seperate hotwire off the battery threw a relay is the safest way to go.

Doug
Those statements are just wrong. Blanket statements like that usually are. THE ONLY thing going thru the switch is the headlight power line, so unless you wire into the headlight power any other wires in the bucket are not going to affect the switch operation. Nothing else goes out other than the headlight when you hit the switch so therefore nothing else is going thru the switch. Just look at the electrical diagram its only the headlight power. In addition, the headlight power line is fused at 10A, I don't know of anyone that adds directly to the headlight line and also ups the fuse to compensate for the addition. That switch is on a 10A fused line so by safety design standards the switch would be required to handle at least 10A.

The issue is cycles. Everything electro/mechanical has a life cycle. Everyone knows when you throw a switch you get a little arc, a light switch at home, an electric drill, just disconnect the battery in the dark and touch the terminal with the cable and even the odo holding current will give a little snap. You do this enough times at several amps and the surface of the connection erodes away, continuing the surface erosion you end up with a smaller conduction path, at some point the surface area can't handle the current and now you have excess heat caused by the resistance, current trying to conduct thru too small of an available path.

Regarding the relays, not everything requires a relay which is why many electrical accessories don't have them. It all comes down to what end function you desire and then design it soundly to meet that function. Other than the engine electrical requirements everything else is considered an electrical accessory on a vehicle. For example our horn works absolutely perfectly without a relay, but a lot of vehicles have a horn relay, put a stebel on an x and it is a good idea to do it through the relay. Why doesn't our horn have a relay? because the horn switch is adequate to handle the current of our little squeaker so a relay is not required. Stebel startup current is pretty high so you don't want to run it thru the stock switch.

I could give a lot of examples where a relay is desirable and where it isn't. For simplicity a relay is a switch and in automotive uses its primary purpose is to act as a switch, either as the main switch or to protect (bypass) a smaller switch. If you don't want/need it switched or the existing switch is adequate in size then a relay is not needed.

A CB radio for example. I wouldn't want that switched through a relay because I want to be able to still use it if I'm broke down on the side of the road without turning the key on. And it doesn't need another switch since it already has its own correct rated switch built in. Similar with my accessory power port, I don't want it switched because I plug the tender in there, I've used it a few times with my air compressor for flats, and I run my computer through an inverter off it when I'm in the tent. It is direct fused to battery.
the start switch is not adequate thats why i recommended the relay. and thats why they melt
Those statements are just wrong. Blanket statements like that usually are. THE ONLY thing going thru the switch is the headlight power line, so unless you wire into the headlight power any other wires in the bucket are not going to affect the switch operation. Nothing else goes out other than the headlight when you hit the switch so therefore nothing else is going thru the switch. Just look at the electrical diagram its only the headlight power. In addition, the headlight power line is fused at 10A, I don't know of anyone that adds directly to the headlight line and also ups the fuse to compensate for the addition. That switch is on a 10A fused line so by safety design standards the switch would be required to handle at least 10A.

The issue is cycles. Everything electro/mechanical has a life cycle. Everyone knows when you throw a switch you get a little arc, a light switch at home, an electric drill, just disconnect the battery in the dark and touch the terminal with the cable and even the odo holding current will give a little snap. You do this enough times at several amps and the surface of the connection erodes away, continuing the surface erosion you end up with a smaller conduction path, at some point the surface area can't handle the current and now you have excess heat caused by the resistance, current trying to conduct thru too small of an available path.

Regarding the relays, not everything requires a relay which is why many electrical accessories don't have them. It all comes down to what end function you desire and then design it soundly to meet that function. Other than the engine electrical requirements everything else is considered an electrical accessory on a vehicle. For example our horn works absolutely perfectly without a relay, but a lot of vehicles have a horn relay, put a stebel on an x and it is a good idea to do it through the relay. Why doesn't our horn have a relay? because the horn switch is adequate to handle the current of our little squeaker so a relay is not required. Stebel startup current is pretty high so you don't want to run it thru the stock switch.

I could give a lot of examples where a relay is desirable and where it isn't. For simplicity a relay is a switch and in automotive uses its primary purpose is to act as a switch, either as the main switch or to protect (bypass) a smaller switch. If you don't want/need it switched or the existing switch is adequate in size then a relay is not needed.

A CB radio for example. I wouldn't want that switched through a relay because I want to be able to still use it if I'm broke down on the side of the road without turning the key on. And it doesn't need another switch since it already has its own correct rated switch built in. Similar with my accessory power port, I don't want it switched because I plug the tender in there, I've used it a few times with my air compressor for flats, and I run my computer through an inverter off it when I'm in the tent. It is direct fused to battery.
There has been many, many,many in the past that have burnt that switch up in the past from adding accessories by connecting into power in the headlight bucket and that is why I strongly encourage everyone to run a seperate Hotwireoff the battery triggered by a relay.
The bike wiring is just not capable of handling a bigger load.
If that switch is burnt then you absolutely have something wired wrong.
Lots of folks with stock lighting/electrical accessory set ups have had starter switch failure. It's not always indicative of something being wired wrong. I think it's just a weak/poor switch from the factory.

EDIT: It seems to be a hit or miss problem too. Some have it and some don't. I'd be exceedingly interested to see if the bikes are from a certain production run or something to that effect, where the batch of switches used is lower quality or has some defect in the manufacturing process.
Lots of folks with stock lighting/electrical accessory set ups have had starter switch failure. It's not always indicative of something being wired wrong. I think it's just a weak/poor switch from the factory.

EDIT: It seems to be a hit or miss problem too. Some have it and some don't. I'd be exceedingly interested to see if the bikes are from a certain production run or something to that effect, where the batch of switches used is lower quality or has some defect in the manufacturing process.
i just got a new switch and the material the contacts are made of is different
i just got a new switch and the material the contacts are made of is different
How much wire is on the new ones? Or does it make up in the switch housing?
How much wire is on the new ones? Or does it make up in the switch housing?

the new switch is comes as the entire control housing the kill switch start switch clam shell housing wires for the brake switch and the harness the goes into the headlight bucket
no headlight and no start. the starter switch is bad. the switched needs to be removed and cleaned and also the guides for the shunt need to be fixed. the overheating of the switch melts the plastic guides and prevents the shunt from sliding up and down. it sticks in the down position and stops the headlight ans starter from working. when you get the switch working again you should put your headlight on a relay to remove the power draw through the switch.]

[/QUOTE

:agree: 100%. This should fix it. If it is something else and this didn't fix it, don't worry this needs to be done anyway.
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the start switch is not adequate thats why i recommended the relay. and thats why they melt
:agree: Even with just the headlight on the circuit, mine burned up with only 7k on the bike. The headlight alone, I think draws 6 or 7 amps. With a solid state relay installed, the switch will draw for less than 1 amp. Probably in the neighborhood of 0.1 amp. This should never burn up. You could light up a christmas tree and not affect the switch.
There has been many, many,many in the past that have burnt that switch up in the past from adding accessories by connecting into power in the headlight bucket and that is why I strongly encourage everyone to run a seperate Hotwireoff the battery triggered by a relay.
The bike wiring is just not capable of handling a bigger load.
Shown is the complete power loop back to the battery of the 3 pin accessory connector located in the headlight bucket and the starter switch is also circled. So explain in electrical terms how it is possible to connect something to that conector in the headlight bucket and have it affect the starter switch in any way or even how it could affect any of the wiring since that line is fused.

In this post alone a number of common posters mentioned their switch has burned up even with nothing extra connected to it. So when a switch burns up, how is it that you determined the fault is with the lightbar on the 3 pin connector unrelated to the start switch in any way and not just another switch getting burned up from normal use.

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Enduro: Stop bringing logic to the party. . there's no room for crap like that on the internet. :thumbup::joke:


Good post. Excellent schematic.
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