Komatsu PC130-7, Shop Manual

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20-322
PC130-7
TROUBLESHOOTING
Error code [203] (Short circuit in swing holding brake solenoid)
User code Error code
Trouble
Short circuit in swing holding brake solenoid
(Governor and pump controller system)
E03 203
Contents of
trouble
• When the signal is output to the swing holding brake solenoid circuit, an abnormal current flows.
Action of
controller
• Turns the output to the swing holding brake solenoid circuit OFF.
• Even if the cause of the failure disappears, the system does not reset itself until the starting switch is
turned OFF.
Problem that
appears on
machine
• The machine cannot swing (The swing holding brake is not released).
Related
information
• The operation state (ON/OFF) of the swing holding brake solenoid can be checked with the monitoring
function. (Code: 023, Center of upper line)
• If the solenoid and wiring harness are normal, the machine can swing by setting the swing holding brake
release switch in the FREE position. (The swing holding brake does not operate when the machine
stops swinging, however.)
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1
Defective swing holding
brake solenoid (Internal
short circuit)
a
Prepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
V05 (male) Resistance
Between (1) and (2) 20 – 60
z
Between (2) and chassis ground Min. 1 M
z
2
Short circuit with chassis
ground in wiring harness
(Contact with ground cir-
cuit)
a
Prepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
Between C03 (female) (37) – D01 – J02 – X05
– V05 (female) (1) or S25 (female) (8) wiring
harness and chassis ground
Resistance
Min. 1 M
z
3
Defective governor and
pump controller
a
Prepare with starting switch OFF, then start engine and carry out trou-
bleshooting.
C03
Left work equipment
control lever
Voltage
Between (37) and
chassis ground
Neutral position Max. 1 V
Swing position 20 – 30 V
[203]
(1)