Help, my starter won't stop running.

While I was out riding yesterday I noticed a screeching noise coming from my WR while I was riding. I was going down a hill so it took me about 10 seconds to get it stopped. Once I killed the engine I noticed the starter wanted to run constantly, if the on/off button was on the starter would run, in gear, clutch in or out, nothing would stop it. I removed the starter button my my bars thinking that breaking the ground through the bars would fix the problem but no luck. Finally I ended up removing the positive terminal to my battery (was there a fuse that would have worked?) and kick starting my WR to get back to my truck.

I did a search of the forums but didn't find much, is this a known issue on 03 WR450s? I need to find out how to fix the issue, and if my starter is allready garbage or if I can fix it. Any help would be appreciated.

Forgot to mention this in my original post, but I was riding in the rain and through some knee high puddles, not sure if it's relevant.

The '03's are notorious for having starter issues, though this is the first time I've heard of a runaway. There was a free upgrade from Yamaha that came out in '04 due to the frequency of issues with the '03. I believe it involved a simple upgrade to '04 parts and the problem was resolved. Do a search using "woodruff key", "'03 starter", and other combinations and you should come up with a bunch of stuff. Hopefully Indy will chime in as he is intimately familiar with the problem...SC

First, do you have a manual? There should be a starter relay that might be giving you a head ache.

You are going to need a voltage meter or test light (meter is better). Check to see if there is a constant power at the starter relay (little unit that the battery positive runs to and then out of to the starter) (disconnect the lead at the starter and tape up so its not wanting to run all the time) there should be a small lead that runs to this to basically switch it on and off with the push of your starter button this is where you want to check for power. If there is power there, you have a problem before the relay (starter button or?) if there is no power available you might have a stuck starting relay.

This is pretty much a quick shot at troubleshooting.

I'll check that out, though I have a feeling that since I'm not the original owner I'll have a hell of a time getting anything free from Yamaha, even a fix.

Pretty much every thread I see on the 03 starter issues is woodruff key related but I didn't think that could have anything to do with a runaway starter. I was thinking more of a solenoid/electrical issue since I was riding in the rain and mud. Then again, I don't know the first thing about the electrical systems on these bikes.

This one most likely has nothing to do with the '03 issues. Pull the fuse and see if it still does it. If so then the starter relay is probably shorted. If not it could be the starter cut-off relay or a short in the harness. Shouldn't be too hard to figure out with a meter. As for damage done it's hard to tell but it probably didn't do the starter any good. You may want to disassemble the starter and give it look.

First, do you have a manual? There should be a starter relay that might be giving you a head ache.

You are going to need a voltage meter or test light (meter is better). Check to see if there is a constant power at the starter relay (little unit that the battery positive runs to and then out of to the starter) (disconnect the lead at the starter and tape up so its not wanting to run all the time) there should be a small lead that runs to this to basically switch it on and off with the push of your starter button this is where you want to check for power. If there is power there, you have a problem before the relay (starter button or?) if there is no power available you might have a stuck starting relay.

This is pretty much a quick shot at troubleshooting.

Excellent, I'll check that out tonight. Sure sounds like a good place to start looking. From your description, it sounds like the starter relay is right in front of the battery, underneath the fuses? Either way, I have a manual and a meter and can check it out tonight.

This one most likely has nothing to do with the '03 issues. Pull the fuse and see if it still does it. If so then the starter relay is probably shorted. If not it could be the starter cut-off relay or a short in the harness. Shouldn't be too hard to figure out with a meter. As for damage done it's hard to tell but it probably didn't do the starter any good. You may want to disassemble the starter and give it look.

I did pull the fuses as a quick trailside test, but I was rushing and not thinking clearly and didn't end up checking it as well as I should have. I saw two 10 amp fuses, one of the left side of the bike and one on the right. Pulling the left did not stop the starter from running. Pulling the right stopped it from running when I pressed the on button, but also stopped the on button from lighting up. I probably should have tried kick starting it at that point but not seeing the little red "on" light I assumed the bike wouldn't run like this and put the fuse back, then disconnected the battery.

Start at the starter and work your way back. Either way, if you have a meter and some time, you will be able to figure it out. The starter system on this bike is pretty simple and usually easily fixed.

Keep us posted.

By the way if it is not the starter relay and you have constant power on the little lead, keep moving up the harness checking for shorts, rubbed sections of wire...

And you say you were riding in the rain? You might have a shorted starter switch (it has no ground and if it were shorted, removing it from the bars would do nothing). Easy way to check is to just un plug it as it should just have two wires.

I did pull the fuses as a quick trailside test, but I was rushing and not thinking clearly and didn't end up checking it as well as I should have. I saw two 10 amp fuses, one of the left side of the bike and one on the right. Pulling the left did not stop the starter from running. Pulling the right stopped it from running when I pressed the on button, but also stopped the on button from lighting up. I probably should have tried kick starting it at that point but not seeing the little red "on" light I assumed the bike wouldn't run like this and put the fuse back, then disconnected the battery.

One fuse is a spare and the other protects everything but the starter motor drive. Sounds like the starter relay is working. Check the starter cut-out relay and start looking for a short somewhere.

I suspect the starter relay is sticking after engaging the starter motor.

It is a mechanical sealed relay and therefore subject to such failures. I doubt the cut off relay or circuit is faulty since your problem is not realted to not starting the starter motor but rather stopping it from over running. The fuse is also not an issue since the starter motor is running - means the fuse is working.

The other possibility is the starter push button ( or starter diode) is staying engaged calling for the relay to stay closed and engage the motor continously. Easy to check the starter button by disconnecting it from the harness behind the headlight and jumper the wiring harness connector to engage & disengage the motor. (you said you disconnected the button from the bars but I am not sure if you did it at the wiring harness behind the headlight if so then the button is fine and the starter relay or starter diode may be the problem)

These are the only 2 situations that can be causing this problem ( remove the starter diode from the wiring harness and inspect as per the manual). You may have got water damage in your wiring harness at the starter diode.

I suspect the starter relay is sticking after engaging the starter motor.

It is a mechanical sealed relay and therefore subject to such failures. I doubt the cut off relay or circuit is faulty since your problem is not realted to not starting the starter motor but rather stopping it from over running. The fuse is also not an issue since the starter motor is running - means the fuse is working.

The other possibility is the starter push button ( or starter diode) is staying engaged calling for the relay to stay closed and engage the motor continously. Easy to check the starter button by disconnecting it from the harness behind the headlight and jumper the wiring harness connector to engage & disengage the motor. (you said you disconnected the button from the bars but I am not sure if you did it at the wiring harness behind the headlight if so then the button is fine and the starter relay or starter diode may be the problem)

These are the only 2 situations that can be causing this problem ( remove the starter diode from the wiring harness and inspect as per the manual). You may have got water damage in your wiring harness at the starter diode.

Thanks for putting it in better words.

If the starter button has to be pressed in order that the bike will start, would make me think that is the point of interest. I believe that the button is like a light switch, if the circuit is closed then power can flow to the next thing down the line. I wasn't sure if the button uses the bars as a ground.

good luck

chris

I've been busy all week with work so when I finally got around to troubleshooting my starter today I found it worked fine. Sure looks like a water issue and that once everything dried out it's working fine. Weird.

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