TM 10-3930-659-10 2-2.  CONTROLS AND INDICATORS (Con’t). KEY CONTROL OR INDICATOR FUNCTION 7 Engine Air Filter Lights when engine air filter element requires Restriction Indicator servicing. 8 Caution - Service Lights yellow when certain precautionary oper- Required Indicator ating conditions occur. 9 Hom Button Operates vehicle horn. 10 Hydraulic Filter Lights when hydraulic filter element requires servic- Restriction Indicator ing. 11 Secondary Steering Lights when secondary steering pump motor is Warning Indicator activated.  An audible alarm will also sound. 12 Right Turn Signal Flashes when turn signal switch is positioned for Indicator right-hand turn.  Also flashes simultaneously with left turn signal indicator when emergency flashers are in use. 13 Brake Oil Low Lights if hydraulic pressure in service brake system Pressure Indicator falls below the safe minimum level.  An audible alarm will also sound. 14 Start Switch ON Lights when start switch Is in ON position and the Indicator engine is not running. 15 Parking Brake Lights when parking brake is applied.  An audible Indicator alarm will also sound. 16 Transmission Oil Low Lights if transmission oil pressure drops below safe Pressure Indicator operating range. 17 Left Turn Signal Flashes when turn signal switch is positioned for Indicator left-hand turn.  Also flashes simultaneously with right turn signal indicator when emergency flashers are in use. 18 Fuel Gage Indicates amount of fuel In vehicle’s fuel tank. 2-3