Troubleshooting
Safety, Operation and Maintenance Manual - Aug 2012
6-29
SY115C9/135C/155H Crawler Hydraulic Excavator
Failure
Code
Symptom
Alarm Trigger Condition
26
Boom-up pilot pressure sensor
abnormal
Boom-up pilot pressure collecting volt lower than 0.25 and
higher than 4.75 for 3s
27
Boom-down pilot pressure sen-
sor abnormal
Boom-down pilot pressure collecting volt lower than 0.25 and
higher than 4.75 for 3s
28
Left travel pilot pressure sensor
abnormal
Left travel pilot pressure collecting volt lower than 0.25 and
higher than 4.75 for 3s
29
Right travel pilot pressure sen-
sor abnormal
Right travel pilot pressure collecting volt lower than 0.25 and
higher than 4.75 for 3s
30
Swing pilot pressure sensor
abnormal
Swing pilot pressure collecting volt lower than 0.25 and high-
er than 4.75 for 3s
34
Front pump proportional valve
overcurrent
Front pump proportional valve current higher than 1300mA
for 3s
35
Rear pump proportional valve
overcurrent
Rear pump proportional valve current higher than 1300mA for
3s
36
Front pump proportional valve
undercurrent
Front pump proportional valve current lower than 200mA for
3s and controller PWM output higher than 10V
37
Rear pump proportional valve
undercurrent
Rear pump proportional valve current lower than 200mA for
3s and controller PWM output higher than 10V
38
Front pump proportional valve
Front pump proportional valve feedback current lower than
150mA or higher than 1350mA for 3s and controller PWM
duty output higher than 10V
39
Rear pump proportional valve
Rear pump proportional valve feedback current lower than
150mA or higher than 1350mA for 3s and controller PWM
duty output higher than 10V
40
Hydraulic oil temperature sen-
sor abnormal
Hydraulic oil temperature collecting volt lower than 0.25V or
higher than 4.75V for 3s
41
Coolant sensor abnormal
Coolant temperature collecting resistance lower than 10
Ω
or
higher than 120
Ω
for 3s after 30 minutes since engine start-
ing
42
Fuel level sensor abnormal
Fuel level collecting resistance lower than 10
Ω
or higher than
120
Ω
for 3s
43
Speed sensor abnormal
Speed collecting frequency lower than 100 for 3s under load
44
Fuel control dial abnormal
Fuel control dial collecting volt lower than 0.25V or higher
than 4.75V for 3s
45
CAN bus abnormal
CAN communication monitoring component overtime or reset
characters changed for 3s
Table 6-4