Monitoring Function Does Not Display "Boom Lower" Normally - Komatsu PC130-7 Shop Manual

TROUBLESHOOTING
E-24 Monitoring function does not display "Boom LOWER" normally
• Monitoring function does not display
Trouble
"Boom LOWER" normally.
Related
• 6-bit position of boom LOWER oil pressure switch (Code: 020, Center of upper line)
information
Defective boom LOWER oil
pressure switch
1
(Internal disconnection or
short circuit)
Disconnection in wiring
harness
2 (Disconnection in wiring
harness or defective
contact in connector)
Possible causes
and standard
Short circuit with chassis
value in normal
ground in wiring harness
state
3
(Contact with ground
circuit)
Short circuit with power
4 source in wiring harness
(Contact with 24-V circuit)
Defective governor and
5
pump controller
20-446
(1)
Cause Standard value in normal state/Remarks on troubleshooting
aPrepare with starting switch OFF, then start engine and carry out trou-
bleshooting.
S02 (male)
Between (1) and (2)
aPrepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
Wiring harness between C03 (female) (20) and
S02 (female) (1)
Wiring harness between S02 (female) (2) and
chassis ground (A16)
aPrepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
Between C03 (female) (20) – S02 (female) (1)
wiring harness and chassis ground
aPrepare with starting switch OFF, then turn starting switch ON and car-
ry out troubleshooting.
Between C03 (female) (20) – S02 (female) (1)
wiring harness and chassis ground
aPrepare with starting switch OFF, then start engine and carry out trou-
bleshooting.
Between (10) and
chassis ground
The monitoring function (special function) of the monitor
panel does not display "Boom LOWER" normally.
Right work equipment
control lever
Neutral position
Boom LOWER position
Right work equipment
C03
control lever
Neutral position
Boom LOWER position
E-24
Resistance
Min. 1 Mz
Max. 1 z
Max. 1 z
Resistance
Max. 1 z
Resistance
Resistance Min. 1 Mz
Voltage Max. 1 V
Voltage
20 – 30 V
Max. 1 V
PC130-7