Unique problem

[Ricktaylor]

My Husqvarna YTHK-20-42. will only run with both ground wires to coils disconnected and ignition turned to off.

 

[StarTech]

Are you referring to a YTH 20K42? There are four variations of this mower listed but three uses a Kohler twin. The problem you describing is a coil failure but you will need to replace both coils as steering diodes are failing.

 

[Ricktaylor]

We Yes it’s a KAre you referring to a YTH 20K42? There are four variations of this mower listed but three uses a Kohler twin. The problem you describing is a coil failure but you will need to replace both coils as steering diodes are failing.

Yes it’s a Kohler 20 hp ,

 

[Ricktaylor]

Are you referring to a YTH 20K42? There are four variations of this mower listed but three uses a Kohler twin. The problem you describing is a coil failure but you will need to replace both coils as steering diodes are failing.

Yes it’s a Kohler 20 hp , yes a Kohler 20 hp 7000 series Both new coils were bought on Amazon. Do I need to buy OEM coils? Where are the steering diodes located?

 

[biggertv]

Sounds like a Safety Switch problem Except for the ignition off part. Carb Solonoid needs 12V to supply fuel unless that's had the workaround. I believe the "ground wires" you refer to are the Kill Wires. Some of those circuits are interesting. For example if deck is engaged, Starter is disabled. Seat switch uses the Kill Wire. Ignition switch uses Kill wire. Neutral/Clutch disables starter, Reverse disables Blade clutch IF electric Clutch...On Some Models...
Did the engine work and Recently Quit or did you buy it this way? Has wiring been played with? Was Ignition Switch Replaced? If so stop Now and get the Correct switch. Just because it plugs in doesn't mean it's the Correct switch. I've had to rewire connector before to make a switch work, lot's of folks couldn't figure it out, a Puzzler!