DIAGNOSE ELECTRONIC AND CONTROL
VALVE COMPONENT MALFUNCTIONS
Engine Control Motor (EC Motor)
Engine Control Sensor (EC
Engine rpm Dial
Move fuel injection pump lever.
Senses position of EC motor
Signal to engine and pump
controller to set target engine
speed for injection pump lever
Fuel injection pump lever does not
Loss of EC motor position sensing.
Speed does not change when dial
Whenever key switch is ON,
injection pump lever position is
learned as the slow idle speed
position. Accordingly, engine speed
is controlled afterward from the
learned position which occurred at
Turning engine rpm dial does not
Engine speeds slower or faster than
Speed is held at 1600 rpm.
increase or decrease engine speed.
speed selected by engine rpm dial
(Auto-idle function operates and
and E mode switch. Cannot control
engine stops by turning key switch
01 Service code is displayed
07 Service code is displayed.
Monitor No. 2, EC angle. Typical
Monitor No. 13, Target Engine
voltage for slow idle is 2.5 volts.
Install JT07065 Test Harness.
Install JT07066 Test Harness.
Check for control signal.
Typical voltage for slow idle is 2.5
Engine stopped by fuel shut-off
If EC sensor has failed, engine
speed learning procedure does not
turns over but does not start.
Description of Operation
See Engine Speed Control System
See Engine Speed Learning Control
See Engine RPM Dial Speed
Operation in Group 9010-05.
Circuit Operation in Group 9010-05.
Control Circuit Operation in Group
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