My 300 sportsman burned up the CDI box while trying to start after a couple of months storage. I have tried 3 new boxes and still have no spark. I have a CD disk manual and have checked many things in the troubleshooting area. I have found that the manual wiring color code does not match the quad in all areas. So, I have checked from the troubleshooting manual; #1, Verify 12 volt dc is present on the RED wire on the CDI box, (there is NO red wire going to the CDI box). #2, I cut the black wire coming from the kill switch. The brown wire has a good ground. #3, The manual says to check that at least 10.5 volts is getting to the CDI box when cranking. I assume that this test is on the non existant RED wire? #4, Check coil ground connection between brown and coil mount bolt. My coil is plastic encased and has no connection, however the brown wire is ground. I can fire the coil by swiping a 12 volt jumper over the primary wire. Coil resistance test are within specs. #5, 3rd new CDI box from 2 suppliers.
Cranking tests. I do not have a peak reading vom. Pulser coil resistance is within specs and some output is noted when cranking. I removed the flywheel and bench tested the pulser coil, OK. Stator wiring resistances are within specs.
The ETC circuit is open.
Can I not see the forest for the trees?

 

What color are the wires leading from the stator to the cdi? The manual may show a red wire,but could actually be a red/black,red/green for this Taiwanese made machine.

 

All 3 wires from the stator are white. Pulsor coil wires are Wht / red stripe & blk.

 

Should have a black/red wire somewhere as the Sportsman 300 is the same as the Hawkeye 300 for 2008 and same wiring.Plus the schematic shows the 3 white wires from the stator going to the regulator,not the cdi module..Plus have you checked the 15 amp fuse? Also there is a fusible link that could melt. It supplies power to the fuse holder.

 

You are quite right abut the 3 white wires going to the regulator, oops. Yes there is a blk / red wire going to the cdi box. It appears to provide power turu the kill switch. The blk/red wire changes color to red/wht at the 3 wire connector.
Nobody has messed with the wires except me. I bought the quad new and it has a whopping 650 miles on it. It has always been hard to start and I have replaced the battery many times.

 

Regulators were the most common thing on the Hawkeye 300 and Sportsman 300 to fail. Have you checked the charging rate at an idle or a little above? Should be 14 volts or so.If lower than that the battery voltage can be weak and cause hard starting.Plus the battery itself.Have you load tested it as a weak or open cell in the battery can cause hard starting.

 

I have done no testing of the charging system in the past, can't now of course because it will not run. I have resorted to a jumper battery in the past, was not using a jumper when the cdi box let the smoke out.

 

Regulator may well be the problem if you have to use a jumper battery. Load test the battery to confirm if it's good or needs to be replaced.You can do a generalized test on the white stator wires leading to the regulator. Should be a small resistance between each white wire and NO white wire should short to ground.Plus there is a test on charging in the manual. If you can at least get it started,then check charging rate back to the battery. If lower than 14 volts,then the regulator may be the cause of all the problems to begin with. Jumping off batteries can burn up cdi modules and just create another problem on top of regulators.

 

I have already tested the stator. All resistances are within specs, open to ground. Checking the manual now to see if there is any way to test the regulator.

 

You can do generalized test also on the regulator wires corresponding with the 3 white stator wires and see if there is resistance between each other. Best way is to still check charging rate when running at an idle and slightly above.