5-12. WARNING LAMPS AND ALARMS .
a. Description. The following warning lamps and alarms are employed in this vehicle series:
(1) ENGINE TEMPERATURE warning lamp.
(2) ENGINE OIL LOW warning lamp.
(3) LOW AIR PRESSURE warning lamp.
(4) BACKUP ALARM (M916 THRU M9ZO).
The ENGINE TEMPERATURE warning lamp is actuated when the water temperature sensing switch
closes (at 225° F, 95°C) if the ignition switch is ON. The ENGINE 0IL LOW warning lamp is actuated
when the engine oil pressure sensing switch closes (at 5 psi, 100 kPa) if the ignition switch is ON. The
LOW Al R PRESSURE warning lamp and buzzer are actuated when the low air switch closes (between
64 and 76 psi) if the ignition switch is ON. The backup alarm goes off when the backup switch is closed
and the ignition switch is ON unless the manual backup alarm override switch is open. The circuits for
these devices are shown in figure 5-29. Wire connection points and wire identification numbers are
Figure 5-29. Warning Lamp and Alarm Circuits