Komatsu PC200-8M0, Shop Manual, Page: 764 / 1254

304 Troubleshooting by failure code, Part 4
Failure code [DW45KA] Swing Brake Sol. Valve Open Circuit
40-304
40
PC200, 200LC, 220, 220LC-8M0
SEN06136-00
Failure code [DW45KA] Swing Brake Sol. Valve Open Circuit
Action
level
Failure code
Failure
Swing Brake Solenoid Valve Open Circuit
(Pump controller system)
L03 DW45KA
Detail of failure
q
Controller output voltage to solenoid is above standard value when pump controller does not drive
swing holding brake solenoid, so pump controller determines that open circuit exists in swing hold-
ing brake solenoid circuit.
Action of con-
troller
q None in particular. (Since no current flows, solenoid is not energized, so swing holding brake is kept
applied.)
q If cause of failure disappears, machine becomes normal by itself.
Problem on
machine
q Upper structure does not swing (swing holding brake is not released).
Related infor-
mation
q
If solenoid and wiring harness are normal, swing operation is possible by setting swing brake can-
cel switch to RELEASE position. (However, swing holding brake is not released while upper struc-
ture is stopped. swing holding brake continues to be applied.)
q
Set swing brake cancel switch to RELEASE position during troubleshooting. When starting switch
is turned to ON position in this condition, normally current can flow in swing holding brake solenoid
circuit and break can be released.
q
Controller command (ON/OFF) to swing holding brake solenoid can be checked with monitoring
function. (Code: 02300 Solenoid 1)
q
Method of reproducing failure code: Turn starting switch to ON position.
q
Swing brake solenoid circuit is powered from pin (101) of pump controller connector C02 or No.1
of fuse box F01.
Cause Procedure, measuring location, criteria and remarks
1
Blown fuse No. 1 (right top fuse) in
fuse box F01
If fuse is blown, see failure code [DW45KB] .
2
Defective swing holding brake
solenoid
1. Turn starting switch to OFF position.
2. Disconnect connector V03, and connect T-adapters to male side.
Between V03 (male) (1) and (2) Resistance 20 to 60
z
3 Defective diode array D01 or D03
1. Turn starting switch to OFF position.
2. Remove diode arrays D01 and D03, and connect T-adapters to each male
side.
a
Check the continuity in diode range.
Between D01 (male) (3) (+) and (7) (-) No continuity
Between D01 (male) (7) (+) and (3) (-) Continuity
Between D03 (male) (3) (+) and (7) (-) No continuity
Between D03 (male) (7) (+) and (3) (-) Continuity
4
Open circuit in wiring harness
(wire breakage or defective con-
tact of connector)
1. Turn starting switch to OFF position.
2. Remove diode D01.
3. Disconnect connector C02 and connect T-adapters to each female side.
a
Swing lock switch OFF position.
Between C02 (female) (101) and D01 (female) (7) Resistance Max. 1
z
Between D01 (female) (3) and C02 (female) (115) Resistance 20 to 60
z
a
If no failure is found by above checks, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connectors D01, C02, and V03, and connect T-adapters to
each female side.
Between D01 (female) (3) and V03 (female) (1) Resistance Max. 1
z
Between V03 (female) (2) and C02 (female) (115)
or (117) or (120)
Resistance Max. 1
z
5 Defective pump controller
If no failure is found by above checks, pump controller is defective. (Since this
is an internal defect, troubleshooting cannot be performed.)