Figure 1-12. Instrument Panel'

TM 10-3930-623-12

1-43. The oil pressure sending unit is connected into the

1-45. INSTRUMENT PANEL (See figure 1-12). The

pressure side of the lubricating oil system. This unit

instrument panel assembly incorporates the usual

contains a coil, the resistance of which varies with

standard instruments in a compact group. The engine

pressure. Actuating current to the instrument passes

operation hourmeter is used to determine when periodic

through this resistance coil which varies the current, and

service operations are due. in addition to controlling the

thus the indication, in proportion to the pressure on the

ignition system, the ignition switch energizes the

sending unit.

instruments, and the starter circuit up to the starter

button. The light switch operates the spot light and

1-44. The water temperature sending unit is threaded

taillight.

into the engine cylinder head to sense and respond to

engine coolant temperature.

This unit contains a

1-46. The fuses in the fuse holder protect the various

temperature sensitive resistance coil which regulates the

electrical circuits of the truck. Refer to the wiring

flow of actuating current to the engine temperature gage

diagram (figure 1-11) for identification of each fuse.

in proportion to engine coolant temperature (see figure

1-47. The instrument voltage regulator is a small voltage

divider which reduces system voltage to six volts for

instrument power.

Figure 1-12. Instrument Panel'

1-13/14