Yes the forward and reverse switches are optical switches. its possible that they could be fouled by dirt or a forigen object, but it is more likly that one is broken. The crown RR 5000/5200 series trucks have built in diagnostic tools that can be used to test the operation of the swithes and potentiometers, you can view the operation of the switches on the acces 1 display screen. Do you know how to use that function?
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