TM 10-3930-659-10 2-2.  CONTROLS AND INDICATORS (Con’t). CONTROL PANEL KEY CONTROL OR INDICATOR FUNCTION 19 Instrument Panel Operates instrument panel light. Light Switch 20 Blackout Lights Operates blackout lights and markers. Switch 21 Engine Hourmeter Shows engine hours of operation. 22 Rear Worklight Operates two rear worklights. Switch 23 Front Wiper/Washer Operates front windshield wiper and washer. Switch 24 Rear Wiper/Washer Operates rear window wiper and washer. Switch 25 Clutch Cut-off Switch Operates transmission cut-off clutch and left brake pedal operation. 26 Driving Lights Switch Operates vehicle driving lights. TA704474 2-4