A few months ago, I started having problems with the ignition switch on my DX33. The key began turning hard and not long after, the starter motor would not engage but the solenoid would click. Sometimes it would even blow the fuse.
I replaced the switch with $14.00 after market unit and it works great. You can use a switch with either 3 or 4 terminals. Here is how to connect the switch.
For a 3 terminal switch:
Cut the factory connector off the wiring harness.
Connect the 2 RED wires together and solder on a terminal eye.
Connect this eye to the terminal on the switch labeled BATTERY.
Solder a terminal eye on the ORANGE wire and connect to the terminal labeled IGNITION.
Solder a terminal eye on the WHITE wire and connect to the terminal labeled STARTER.
A 4 terminal switch will have an extra terminal labeled ACC.
You do not need to connect anything to this terminal unless you want to run any accessories such as a radio, ect...
I used the 4 terminal switch but did not use the ACC terminal. This way, when I trailer my tractor, I can turn the key to ACC and the key can not fall out of the switch like it can in the off position.