[dtobin80]

Hello, I have a 99 Polaris Magnum 500 that I'm stumped with. There are 3 black wires (kill switch circuit I think) that go to 1 black coming from the CDI. I've isolated each of the 3 from the black side and connected them 1 at a time and each one kills the bike. I've traced them to the all wheel drive switch, to the start/stop switch and to and to the speedometer. The blackwire isn't damaged on any of those 3 circuits. I also cleaned the connections. Can somebody please tell me what I might be missing? It will start if I leave that black wire from the cdi disconnected from the other 3. Thanks in advance.

 

[FPD218]

Welcome to the forum

 

[latebird]

There is 4 kill devices - you have found two - the wire going to the throttle housing is not to the AWD switch, but the Throttle Safety Switch - if there is continuity to ground on any of the black wires, it will kill spark - disconnecting the black wire from the CDI is testing the ignition system - you have proved the ignition is working, now you need to fix the kill circuit.

One of these 4 devices is connected to ground and killing the spark; 1) key switch, 2) handlebar kill switch, 3) throttle safety switch, 4) the speedometer (the reverse speed limiter is built into the speedo and can connect the black wire to ground if it fails in a specific way).

 

[SubaruSlayer]

Someone is getting a ground connection when it shouldn't be. If I remember those 3 wires are spliced together, so if one of the components is or isn't doing its job, it shouldn't matter which of the 3 wires you try. The most common culprit is the throttle adjustment, pop off the throttle cover and see if the two wires are connected with the throttle closed, they shouldn't be. It's a safety in case the throttle cable breaks it will kill the bike.
It's unlikely but possible that the kill switch or ignition switch have failed. Do the switches feel sticky or bind at all when you move them? Also, do you have access to a multimeter?

 

[dtobin80]

Welcome to the forum

Thank you!

There is 4 kill devices - you have found two - the wire going to the throttle housing is not to the AWD switch, but the Throttle Safety Switch - if there is continuity to ground on any of the black wires, it will kill spark - disconnecting the black wire from the CDI is testing the ignition system - you have proved the ignition is working, now you need to fix the kill circuit.

One of these 4 devices is connected to ground and killing the spark; 1) key switch, 2) handlebar kill switch, 3) throttle safety switch, 4) the speedometer (the reverse speed limiter is built into the speedo and can connect the black wire to ground if it fails in a specific way).

There is 4 kill devices - you have found two - the wire going to the throttle housing is not to the AWD switch, but the Throttle Safety Switch - if there is continuity to ground on any of the black wires, it will kill spark - disconnecting the black wire from the CDI is testing the ignition system - you have proved the ignition is working, now you need to fix the kill circuit.

One of these 4 devices is connected to ground and killing the spark; 1) key switch, 2) handlebar kill switch, 3) throttle safety switch, 4) the speedometer (the reverse speed limiter is built into the speedo and can connect the black wire to ground if it fails in a specific way).

I have separated all 3 of the black wires and tested them separately. All 3 are showing continuity to ground which is why I am baffled. I traced all 3 start to finish and no damage was found.

Someone is getting a ground connection when it shouldn't be. If I remember those 3 wires are spliced together, so if one of the components is or isn't doing its job, it shouldn't matter which of the 3 wires you try. The most common culprit is the throttle adjustment, pop off the throttle cover and see if the two wires are connected with the throttle closed, they shouldn't be. It's a safety in case the throttle cable breaks it will kill the bike.
It's unlikely but possible that the kill switch or ignition switch have failed. Do the switches feel sticky or bind at all when you move them? Also, do you have access to a multimeter?

Brand new start/kill headlight switch. Throttle Safety wire cut. But now only 2 of the 3 black wires are killing the bike. It's the one from the speedometer!
Before cutting the throttle safety all 3 did the same thing. Thank you! Now what, lol

 

[dtobin80]

Yes I have a multimeter. Can simply leave the black lead from the speedo cut? Or do I need to replace the speedo. This is a ranch workhorse, the speedometer isn't important to me

 

[polman500]

Yes I have a multimeter. Can simply leave the black lead from the speedo cut? Or do I need to replace the speedo. This is a ranch workhorse, the speedometer isn't important to me

Do you need 4x4? It can be jumpered if you do and don't want to replace the speedo.

 

[dtobin80]

Do you need 4x4? It can be jumpered if you do and don't want to replace the speedo.

Yes, 4x4 is a must. I would love the ability to toggle back-and-forth between 4 wheel and 2 wheel (a toggle switch maybe). but if I had to pick one it would be 4x4.

 

[latebird]

You can cut the black wire from the speedo and the only effect will be the failure of reverse speed limiting - 4x4 will be unaffected

 

[dtobin80]

You can cut the black wire from the speedo and the only effect will be the failure of reverse speed limiting - 4x4 will be unaffected

Perfect, thank you!

 

[SubaruSlayer]

I've had a cheap china CDI box fail sometime last month, that may be your culprit. In my case I had to either overcome the circuit with an 80A battery charger or ground the black wire on/off a bunch of times to get the bike to start and leave the wire disconnected. If it were connected the bike would die, which is super weird that's what it took to get it running.

 

[latebird]

I've had a cheap china CDI box fail sometime last month, that may be your culprit. In my case I had to either overcome the circuit with an 80A battery charger or ground the black wire on/off a bunch of times to get the bike to start and leave the wire disconnected. If it were connected the bike would die, which is super weird that's what it took to get it running.

Uh........... How did an 80A battery charger help when the ignition is AC (magneto) and does not need battery energy to have spark? I don't understand, but I am willing to learn.

 

[SubaruSlayer]

Me neither, to be honest. That's how they were getting their machine to start. Once it was running, it did fine on its own power until they shut it down again. If I were to guess I'd suspect an Internal short in the CDI box between the kill wire and one of the capacitor coil things, who knows?

 

[latebird]

If I were to guess (and I am) I think the starter motor was faulty and needed high voltage to crank the engine fast enough to start. That could be verified by using the recoil starter - if it started easily with the recoil, then the starter motor was faulty - if it could not be started using the recoil, then I would guess the compression was low and it had to be cranked above 850 RPM to start (faster cranking raises the compression) - then if it died by plugging in the black wire, one of the 4 engine kill circuits was connected to ground.

Who knows? Any knowledgeable mechanic would know and fix the problem in short order.