Guardian Technologies 4758, 4456, 4390, 4389, 4760, 4759 manual Engine Shutdown

SECTION 4.2

OPERATIONAL ANALYSIS

PART 4

DC CONTROL

ENGINE SHUTDOWN

Following retransfer back to the "Utility" source, an "engine cool-down timer" on the circuit board starts timing. When that timer has timed out (approximately one minute), circuit board action will de-energize the circuit board’s run relay

(K2). The following events will then occur:

The DC circuit to Wire 14 and the fuel solenoid (FS) will be opened. The fuel solenoid (FS) will de-energize and close to terminate the engine fuel supply.

The hourmeter (if equipped) connected to Wire 14 will be opened and clock function of the hourmeter will stop.

The battery charge relay (BCR) connected to Wire 14 will be de-energized. This will cause transformer (TX) voltage to power the battery charger again.

Circuit board action will connect the engine’s ignition shutdown module (ISM) to ground, via Wire 18, circuit board Pin 13, and Wire 0. Ignition will be terminated.

Without fuel flow and without ignition, the engine will shut down.

Figure 7. Circuit Condition -

Retransfer to “Utility” and Engine Shutdown

Page 4.2-13