Failure Code [Ca778] Eng Bkup Speed Sensor Error - Komatsu ecot3 PC300LC-8 Shop Manual

SEN02630-05

Failure code [CA778] Eng Bkup Speed Sensor Error

Action code Failure code
E15
Contents of
• There is error in signal from engine Bkup speed sensor.
trouble
Action of con-
• Continues control with signal from engine Ne speed sensor.
troller
Problem that
• Engine does not start easily.
appears on
• Engine output lowers.
machine
Related infor-
• Method of reproducing failure code: Start engine.
mation
Defective sensor power sup-
1
ply 2 system
Defective engine Bkup
2
speed sensor
Breakage or improper clear-
3 ance of engine Bkup speed
sensor
Breakage of rotation sensor
4
ring
Disconnection in wiring har-
Possible causes
ness
and standard
5 (Disconnection in wiring or
value in normal
defective contact in connec-
state
tor)
Ground fault in wiring har-
ness
6
(Short circuit with GND cir-
cuit)
Hot short (Short circuit with
7 5V/24V circuit) in wiring har-
ness
Short circuit in wiring har-
8 ness
(with another wiring harness)
38
Trouble
CA778
Cause
Engine Bkup speed sensor error
(Engine controller system)
Standard value in normal state/Remarks on troubleshooting
If failure code [CA187] is also indicated, carry out troubleshooting
for it first.
a
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
C13 (male)
Between (1) – (2)
Voltage is measured with wiring harness connected. Accordingly, if
voltage is abnormal, check wiring harness and controller, too, for
another cause of trouble, and then judge.
Engine Bkup speed sensor may be broken or may have improper
clearance. Check it directly.
Rotation sensor ring may be broken. Check it directly.
a
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Wiring harness between CE01 (female) (26)
– C13 (female) (3)
a
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Wiring harness between CE01 (female) (26)
– C13 (female) (3) and chassis ground
a
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
Wiring harness between CE01 (female) (26)
– C13 (female) (3) and chassis ground
a
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Wiring harness between CE01 (female) (26)
– C13 (female) (3) and between CE01
(female) (37) – C13 (female) (1)
Wiring harness between CE01 (female) (26)
– C13 (female) (3) and between CE01
(female) (47) – C13 (female) (2)
40 Troubleshooting
Power supply 4.75 – 5.25 V
Resis-
tance
Resis-
tance
Voltage
Resis-
tance
Resis-
tance
PC300, 350-8
1
Voltage
Max. 10 z
Min.
100 kz
Max. 1 V
Min.
100 kz
Min.
100 kz