TM 10-3930-669-10 2-1.  OPERATOR CONTROLS AND INDICATORS (CONT). Table 2-1.  Controls and Indicators - CONT. Key Control/Indicator Function 25 Heater Temperature Control Adjusts temperature of heat to the operator's compartment Turn dial clockwise to increase cab temperature.  Turn dial counterclockwise to decrease cab temperature. 26 Heater Blower Switch Controls heater blower.  Three position switch.  Push switch forward for OFF.  Push switch back once for LOW speed. Push switch back twice for HIGH speed. 27 Cab Lights (2) Illuminate operator's compartment. 28 Fan Speed Switch Controls fan speed.  Two position switch.  Push switch forward for ON.  Push switch back for OFF. 2-6