Komatsu PC200-8M0, Shop Manual

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304 Troubleshooting by failure code, Part 4
Failure code [DHSDMA] Bucket Dump PPC Press Sensor Abnormality
40-304
18
PC200, 200LC, 220, 220LC-8M0
SEN06136-00
Failure code [DHSDMA] Bucket Dump PPC Press Sensor Abnormality
Action
level
Failure code
Failure
Bucket Dump PPC Pressure Sensor Abnormality
(Pump controller system)
L01 DHSDMA
Detail of failure q Signal voltage of bucket DUMP PPC pressure sensor is below 0.3 V or above 4.5 V.
Action of con-
troller
q
Controls machine taking it that bucket DUMP PPC pressure is 0 MPa {0 kg/cm
2
}.
q
If cause of failure disappears, machine becomes normal by itself.
Problem on
machine
q
Automatic deceleration does not cancel.
q Controllability of bucket DUMP deteriorates.
Related infor-
mation
a
If 5 V circuit (3) and ground circuit (1) of pressure sensor are connected inversely, pressure sensor
will be broken. Accordingly, take extreme care when checking.
q
As T-adapter for pump controller connector is "socket-type box", operating voltage cannot be mea-
sured at pump controller connector.
q
Bucket DUMP PPC pressure can be checked with monitoring function.
(Code: 07301 Bucket DUMP PPC pressure)
q
Method of reproducing failure code: Turn starting switch to ON position or start engine.
Cause Procedure, measuring location, criteria and remarks
1
Defective 5V sensor power supply
1 system
If failure code [ DA25KP ] is also displayed, perform troubleshooting for it first.
1. Turn starting switch to OFF position.
2. Disconnect connector P05 and connect T-adapters to female side.
3. Turn starting switch to ON position.
a
If power supply voltage is abnormal, proceed to check on cause 3.
Between P05 (3) and (1)
Power sup-
ply
Voltage 4.5 to 5.5 V
2
Defective bucket DUMP PPC pres-
sure sensor (internal defect)
1. Turn starting switch to OFF position.
2. Insert T-adapters into connector P05.
3. Turn starting switch to ON position.
Between P05 (2) and (1)
Sensor out-
put
Voltage 0.5 to 4.5 V
a
If power supply voltage is normal and sensor output voltage is abnormal, it
is difficult to judge whether cause of failure is defective sensor, ground fault
or hot short circuit in wiring harness. Check as below.
1. Turn starting switch to OFF position.
2. Replace connector P05 with connector of other PPC pressure sensor.
3. Turn starting switch to ON position and display "Abnormality Record"
screen of electrical system on machine monitor.
4. If E mark is not displayed for this failure code, bucket DUMP PPC pressure
sensor is defective.
a
After finishing test, restore connectors.
3
Open circuit in wiring harness
(wire breakage or defective con-
tact of connector)
1. Turn starting switch to OFF position.
2. Disconnect connectors C01 and P05, and connect T-adapters to each
female side.
a
If power supply voltage measured in check on
cause 1 is normal, this check is not required.
Between C01 (female) (18) and P05 (female) (1)
Resistance Max. 1
z
Between C01 (female) (34) and P05 (female) (2) Resistance Max. 1
z
a
If power supply voltage measured in check on
cause 1 is normal, this check is not required.
Between C01 (female) (9) and P05 (female) (3)
Resistance Max. 1
z
4
Ground fault in wiring harness
(contact with ground circuit)
1. Turn starting switch to OFF position.
2. Disconnect connectors C01 and P05, and connect T-adapters to either
female side.
Between ground and C01 (female) (34) or P05
(female) (2)
Resistance Min. 1 M
z
5
Hot short circuit in wiring harness
(contact with 24 V circuit)
1. Turn starting switch to OFF position.
2. Disconnect connector P05.
3. Connect T-adapters to female side of connector P05.
4. Turn starting switch to ON position.
Between P05 (female) (2) and ground Voltage Max. 1 V