Failure Code [Ca731] Abnormal Phase In Engine Bkup Speed Sensor - Komatsu Galeo BR380JG-1E0 Shop Manual

SEN02093-00

Failure code [CA731] Abnormal phase in engine Bkup speed sensor

User code Failure code
E15 CA731
Contents of
• Phase error was detected in signals from engine Ne speed sensor and engine Bkup speed sensor
trouble
Action of
• Continues control with signal from engine Ne speed sensor.
controller
Problem that • Engine does not start at all or does not start easily.
appears on • Idle speed is unstable.
machine • Exhaust gas becomes black.
Related
• Method of reproducing failure code: Start engine.
information
Breakage of engine Ne
1
speed sensor
Breakage of engine
2
Bkup speed sensor
Defective installation or
breakage of rotation
3
sensor wheel on crank-
shaft side
Possible
causes and
Defective installation or
standard value
breakage of rotation
4
in normal state
sensor ring on cam-
shaft side
Defective timing of
5 crankshaft and cam-
shaft
Defective connection
6
of ground terminal
30
Abnormal phase in engine Bkup speed sensor
Trouble
(Engine controller system)
Cause Standard value in normal state/Remarks on troubleshooting
Engine Ne speed sensor may be broken. Check it directly.
Engine Bkup speed sensor may be broken. Check it directly.
Rotation sensor wheel on crankshaft side may be installed defectively or
broken. Check it according to the following procedure.
1) Set No. 1 cylinder at compression top dead center (Match stamped
mark).
2) If center of oblong hole of rotation sensor wheel is at tip of Ne speed
sensor, rotation sensor wheel is installed normally.
Rotation sensor ring on camshaft side may be installed defectively or bro-
ken. Check it according to the following procedure.
1) Set No. 1 cylinder at compression top dead center (Match stamped
mark).
2) Remove Bkup speed sensor.
3) If 2 grooves (1 crest) of rotation sensor ring are seen through sensor
mounting hole, rotation sensor ring is installed normally.
Timing of crankshaft and camshaft may be defective. Check it directly.
Ground terminal may be connected defectively. Check following terminals
directly.
• Ground terminal of machine ((–) terminal of battery)
• Ground terminal of engine
• Ground terminal of engine controller
• Ground terminal of starting motor
40 Troubleshooting
1
BR380JG-1E0