Fiat Kobelco EX355 Tier2, Technical Manual

Page: 330 / 968

EX355 T5-4-57
TROUBLESHOOTING B
Monitor travel motor
swash angle. After
installing a pressure
gauge to solenoid
valve unit (SI) port,
repeat traveling and
stopping. Check if the
pressure value
displayed on Dr. EX
equals to the pressure
gauge reading and that
both vary identically.
NO
YES
Disconnect
harness from
solenoid valve
unit (SI). Connect
test harness
(75301514)
between solenoid
valve unit (SI)
and the
disconnected
harness. Check
when travel
mode selector is
actuated, the
solenoid valve
control voltage is
present.
•
Travel mode: Fast
•
Monitor item: Travel motor swash
angle control pressure
•
Travel mode: Fast
•
Measurement: Refer to Operational
Performance Test section.
NO
YES
Faulty travel
pressure switch,
broken harness
between travel
pressure switch
and MC, or
clogged filter in
travel pilot signal
circuit.
Faulty solenoid
valve unit (SI).
Broken harness
between solenoid
valve and MC.
Faulty travel
motor or travel
reduction gear.
YES
NO
NOTE - The measurement of the control voltage of proportional solenoid valves SG, SI, SD and SC, must be
performed with test harness (75301514) meaning that the main controller (MC) output must be connected
to the load of the solenoid valve. Under this test configuration, the normal control voltage changes from
5 through 10 Volt.
On the other hand, when measuring the control voltage directly on the connector disconnected from the
solenoid valve (harness side) the voltage measured is always 24 Volt and this is irrelevant in
troubleshooting the solenoid valve.