2012 420fm won't start

welcome to the forums. check the gear position switch wire at the back of the engine/lower end. see if it's connected ?, lose ?, dirty ?, this tells the ecu when its in neutral. yes, you know it's in neutral, cuz ya can roll it ?, but the ecu doesn't see it's in neutral because the gear position switch is not seeing it ? .

Thanks , I did check that I think. Would they be the plug just below the recoil for the pull start ?
I done a bit research and managed to find out how to start it buy piting a wire to the earth but it only starts in first gear and has not solved my problem. I am just pleased to hear it running tho lol
Also read that I should reset the ecu but it only tells you how to do it on the ES model not the FM manual model

Check your gear position switch plug. If any of those connections aren't getting a good connection, you won't get spark.

There is a wire that comes off the back of the motor, and runs up to a square grey plug under your right buttcheek when sitting on the seat. It's a PITA to get the plug apart, but that's where my problem was on an 07 420FM. Mine wouldn't start in 1st, and when I bypassed the plug with a jumper on the 1st gear specific wires, it would start in 1st.

Take the plug apart, clean the connections well, and see if that helps.

Hi: Also recheck the pins on the ECM and connector for corrosion or bent pin.

Hold the brake levers on handlebars when trying to crank. It should crank in gear with them held.

LBZ_Duramax said:

Hold the brake levers on handlebars when trying to crank. It should crank in gear with them held.

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It won't if the gear position switch isn't working or the plug isn't making a good connection.

If the ECU can't tell what gear the machine is in, you get no spark.

Jeepwm69 said:

LBZ_Duramax said:

Hold the brake levers on handlebars when trying to crank. It should crank in gear with them held.

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It won't if the gear position switch isn't working or the plug isn't making a good connection.

If the ECU can't tell what gear the machine is in, you get no spark.

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another reason why I hate stupid electronic crap on todays atvs !..lmao. give me simple...SIMPLE WORKS !..LOL.

Your new 500 is the same way. Interestingly enough, if it's started, it will continue to run.

420's are the same way.

My 09 intermittently doesn't show 3rd gear on the display. If it is in 3rd and 3 is not displayed, it will just turn over and not crank. If the 3 is showing on the display it will crank.

I'm sure it's a loose connection in the gear position switch plug, I just haven't messed with it yet.

Jeepwm69 said:

Your new 500 is the same way. Interestingly enough, if it's started, it will continue to run.

420's are the same way.

My 09 intermittently doesn't show 3rd gear on the display. If it is in 3rd and 3 is not displayed, it will just turn over and not crank. If the 3 is showing on the display it will crank.

I'm sure it's a loose connection in the gear position switch plug, I just haven't messed with it yet.

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the switch can be going out as well.

Thanks for all the replys , I'm away for a few days now so hopefully have enough info here to get it sorted , if it is the switch where a ours is it located is that it inside the engine and comes through the casing at rear

Mickd said:

Thanks for all the replys , I'm away for a few days now so hopefully have enough info here to get it sorted , if it is the switch where a ours is it located is that it inside the engine and comes through the casing at rear

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most neutral/gear position switches are inside the rear engine case, and you only can get to them by removing the rear case, which is the stator case.