TM 5-3805-281-24-1
Theory of Operation
AI (AUTO-IDLE) MODE SPEED CONTROL CIRCUIT OPERATION
9010
05
11
controller. The EC (engine control) sensor (B) sends
The function of the auto-idle mode speed control circuit
an electrical feedback signal to the controller indicating
(H) is to automatically reduce engine speed when all
the motor's position.
dig and propel function are in neutral to reduce fuel
consumption and the noise level. The AI indicator is
Actuating the propel or a dig function causes an
ON when the auto-idle switch (E) is pushed to show
electrical signal to be sent from the propel or dig
that the auto-idle function is actuated. Pushing the
pressure switch to the controller. The controller then
switch again turns the auto-idle function off.
sends an electrical signal to the engine control motor
to increase engine speed back to the setting of engine
When auto-idle function is actuated and no electrical
rpm dial.
signal is received from the propel or dig pressure
switches (F and G) for more than four seconds, the
The parameter for auto-idle engine speed can be
engine and pump controller (D) sends an electrical
change from the factory setting within a specified
signal to the engine control motor (C). The control
range. (See Excavator Diagnostic Software Special
motor reduces the engine speed to the specified
Function--Engine Speed in Group 9025-25.)
auto-idle speed. The electrical signal sent to the motor
is calculated from data stored in the engine and pump
TX,9010,GG2870
1923OCT971/1