TM 5-3805-281-24-1
Theory of Operation
ENGINE RPM DIAL SPEED CONTROL CIRCUIT OPERATION
9010
05
6
The engine speed for slow idle is limited by the
The function of the engine rpm dial speed control
external slow idle stop. The data for slow idle position
circuit (E) is to control engine speed from slow to fast
is stored in the engine and pump controller and is
idle in standard mode in response to the position of
used to calculate the positions for, AI (auto-idle), E
engine rpm dial (A).
(economy), and HP (high power) modes. (See Engine
Learning Control Circuit Operation in this group. For
As the engine rpm dial is turned to increase or
adjustment, see Injection Pump Fast and Slow Idle
decrease engine speed, the electrical signal sent from
Stops Adjustment in Group 9010-20.)
the dial to the engine and pump controller (D)
changes. Then, from data stored in the controller, the
The engine speed for fast idle in standard mode is
controller sends an electrical signal to actuate the
controlled by data stored in the engine and pump
engine control motor (C). The control motor moves the
controller. The parameter for fast idle in standard
injection pump lever by a push-pull cable to change
mode can be change from the factory setting within a
engine speed in response to the position of the engine
specified range. (See Excavator Diagnostic Software
rpm dial. The EC (engine control) sensor (B) sends an
Special Function--Engine Speed in Group 9025-25.)
electrical feedback signal to the controller indicating
the motor's position.
Continued on next page
CED,TX08227,3179
1906JUN981/2
