Instruments and Controls Identification IMPORTANT: If any of the ABS warning lights do not work as described above, or come on while driving, repair the ABS system immedi- ately to ensure full antilock braking capability. See Group 42 of the Heavy-Duty Trucks Ser- vice Manual for troubleshooting procedures. WARNING If the warning system does not activate when the ignition is turned on, repair the system to provide warning protection for oil pressure, coolant tem- perature, and brake system air pressure. See the brake system operating instructions in Chap- ter 6 for more information.
Optional Warning and Indicator Lights VIGIL I Warning System Standard Indicator Lights The most common optional warning and indicator lights ( Fig. 2.19 ) consist of any combination of the following: Standard indicator lights ( Fig. 2.19 ) include: Interaxle differential indicator light, which is standard on all dual-drive vehicles. An indicator light illuminates whenever the interaxle differ- ential is locked out (switch is in the lock posi- tion). 1. The green right- and left-turn signal lights flash on and off whenever the outside turn signal lights are flashing. 2. The green high-beam indicator light comes on when the headlights are on high beam.
Automatic sludge ejector (moisture ejection valve) indicator light. An indicator light comes on whenever the ejector is operating. Standard Warning Lights Utility light(s) indicator light. If utility lights are installed in the back of the vehicle, an indicator light comes on when they are in use. Standard red warning lights ( Fig. 2.19 ) are for oil pressure, water temperature, and low air pressure. Whenever conditions cause one or more of these lights to come on, a warning buzzer also alerts the driver: Mirror heat indicator light. An indicator light comes on whenever the mirror heat switch is on. 1.
The water temperature warning light and buzzer activate whenever the engine coolant tempera- ture exceeds a preset point determined by the engine manufacturer. See the engine manual for this temperature. Low-water warning light, which is standard when a low-water probe warning system or a four-way engine shutdown system is installed. A warning light comes on whenever the coolant level in the radiator drops below the low-water probe. 2. The oil pressure warning light and buzzer acti- vate whenever the oil pressure falls below the minimum oil pressure recommended by the en- gine manufacturer. Fifth wheel slider indicator light.
An indicator light comes on whenever the air-operated lock- pins on a fifth wheel are retracted from the baseplate (the fifth wheel slider is unlocked). 3. The low air pressure warning light and buzzer activate whenever air pressure in the primary or secondary air reservoir falls below 64 to 76 psi (441 to 524 kPa). Optional warning and indicator lights and their loca- tions may vary, because of different optional equip- ment installed. Other optional accessories and stan- dard equipment that are or can be equipped with warning or indicator lights include: engine heater, parking brakes, tire sanders, spotlights, oil level, oil temperature, cruise-control system, engine fan, and other options.
When the ignition is turned on, oil- and air-pressure warnings activate until the engine starts and mini- mum pressures are exceeded. If the low-oil warning light remains lit after running the engine for 15 sec- onds, shut off the engine and determine the cause. See the Heavy-Duty Trucks Service Manual for repair procedures. 2.16