Theory of Operation
ENGINE SPEED LEARNING CONTROL CIRCUIT OPERATION
control) sensor (B). The slow idle position data is
The function of the engine speed learning control
stored in the engine and pump controller.
circuit (G) is to learn the slow idle position as
determined by the slow idle stop bracket on the
The position of the engine control motor for auto-idle
injection pump and to store that data in the engine and
mode, E (economy) mode, and fast idle in standard
pump controller (D).
mode is based on the slow idle position data stored in
the engine and pump controller.
When the engine learning switch (F) is pushed up to
the learning position and the key switch (E) is turned
When the following components are repaired or
on, the engine control motor (C) is driven by an
replaced, or when engine speeds deviate from
electrical signal from the engine and pump controller
specification, the engine control motor adjustment and
(D). The control motor moves the injection pump lever
engine learning control procedure must be performed.
to the slow idle position (the end of slot in slow idle
stop bracket). An electrical feedback signal
corresponding to the slow idle position is sent back to
· Engine speed control cable.
the engine and pump controller by the EC (engine
Continued on next page