Sledjunkyme,
I have an 03 RX 1 mtn also and a manual. To check the switch the manual says to disconnect the coupler under the handle bar cover.
Pull it apart, there are three wires going into the plug. B/L is ground,Lg/W & Lg/L are the hot wires. Use a pocket tester set to check resistance or continuity. The -- negative is always connected to ground B/L. When you connect the + positive to the Lg/W or Lg/L, (and operate the switch) there should continuity or a reading # showing when you move the switch. If no conunity the switch is bad. There should not be any reading or continuity when the switch is not moved.
B/L=Black/Blue
Lg/W=Light green/White
Lg/L=Light green/Blue
Hope this helps you a little,
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