Section 5
ENGINE DC CONTROL SYSTEM
INTRODUCTION
The engine DC control system includes all compo- nents necessary for the operation of the engine. Operation includes off, preheat, cranking/starting, running, shutdown, and fault shutdown. The system is shown schematically.
OPERATIONAL ANALYSIS
CIRCUIT CONDITION- OFF:
Battery voltage is available to the engine controller circuit board from the unit BATTERY and via (a) the RED battery cable, Wire 13, a 14 amp FUSE (F1), Wire 15 and engine controller Terminal 1. However, circuit board action is holding the circuit open and no action can occur.
Battery voltage is available to the contacts of a STARTER CONTACTOR (SC), but the contacts are open.
Battery voltage is available to the contacts of a PRE- HEAT CONTACTOR (PHC), but the contacts are open.
Battery voltage is available to the PREHEAT SWITCH (SW).
The switch is open and the circuit is incomplete. Battery voltage is also available to the remote con- nection for a remote preheat switch.
Battery voltage is available to the BATTERY CHARGE RECTIFIER (BCR). This is used as a return path for Battery Charge Winding current.
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