Right Drive Motor, Faulty Field Drive

Situation
Indication: "18" display. Vehicle operation disabled.

Cause
Faulty right motor field circuit, faulty logic card.

Inspection
Disconnect battery plug.
Check to see if there is shorting near H bridge heat sink.

Check and see if the motor circuit is shorted or open circuit on the right motor, also check for earth faults as it may short out through the chassis of the truck if there is an earth fault.