Travel Speed Does Not Change - Komatsu Galeo PC800-8 Shop Manual

40 Troubleshooting
H-21 Travel speed does not change
Failure

• Travel speed does not change

phenomenon
• Check that the Lo and Hi travel speeds are normal.
(If they are abnormal, carry out the related troubleshooting.)
Relative • The travel speed selection system has the automatic speed changing function. If the oil pressure rises
information above 22.6 MPa {230 kg/cm
is traveling at Hi (Hi is still displayed on the monitor panel).
• Carry out all the troubleshooting in working mode P.
Possible causes
Malfunction of travel speed
and standard 1
solenoid valve
value in normal
state
Malfunction of travel motor
2
(servo mechanism)
PC800, 850-8
2 } during travel, the travel speed is changed to Lo even while the machine
Cause Standard value in normalcy and references for troubleshooting
aPrepare with the engine stopped, then carry out troubleshooting with
the engine at high idle.
Travel speed selection switch
Since the servo mechanism of the travel motor may have a malfunction,
check it directly.
Solenoid valve outlet pressure
Lo
Hi
SEN00794-02
0 MPa {0 kg/cm 2 }
Min. 2.74 MPa
{Min.28 kg/cm 2 }
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