Komatsu PC200-8M0 Shop Manual page 832

SEN06138-00
Cause
Defective starting motor safety
13 relay
(internal defect)
Defective starting motor
14
(internal defect)
Defective alternator
15
(Internal short circuit)
Open circuit in wiring harness
16 (wire breakage or defective con-
tact of connector)
10
40-400
Procedure, measuring location, criteria and remarks
1. Turn starting switch to OFF position.
2. Disconnect cable only from C terminal on starting motor safety relay.
3. Insert T-adapter between male and female sides of connector R17.
4. Turn starting switch to START position and perform troubleshooting.
Between safety relay terminal B and E
Between safety relay terminal R
(R17-2) and safety relay terminal E
Between safety relay terminal S
(R17-1) and safety relay terminal E
Between safety relay terminal C (R28)
and safety relay terminal E
If power supply, input from alternator generation, and starting input to starting
motor normal but starting output to starting motor is abnormal, starting motor
safety relay is defective.
1. Turn starting switch to OFF position.
2. Turn starting switch to START position and perform troubleshooting.
Between starting motor terminal B
(SB) and ground
Between starting motor terminal C
(SC) and ground
If power supply and starting input to starting motor are normal but starting
motor does not rotate, starting motor is defective.
1. Turn starting switch to OFF position.
2. Insert T-adapters into connector E12.
3. Turn starting switch to ON position.
Voltage Between E12 (1) and ground
q
Battery relay
1. Turn starting switch to OFF position.
Between terminal R01 and ground (T08)
q
Battery relay
1. Turn starting switch to OFF position.
2. Turn starting switch to ON position.
a To check to where 24 V is supplied to locate open section
Between terminals R04 and R01
Between terminals R02 and R01
Between terminals R03 and R01
Between terminal R01 and ground
q
Alternator and starting motor
1. Turn starting switch to OFF position.
2. Disconnect battery ground cable.
3. Insert T-adapters into connectors H15, S14, R07, R17, E10, and E12.
4. Connect battery ground cable.
5. Turn starting switch to START position and perform troubleshooting.
a Check to where 24 V power is supplied to isolate open section.
Between H15 (4) and ground
Between S14 (1) and ground
Between S14 (3) and ground
Between R07 (4) and ground
Between R17 (1) and ground
Between E10 (1) and ground
Between alternator B terminal and ground
Between starting motor terminal B and ground
400 Troubleshooting of electrical system (E-mode)
E-1 Engine does not start (Engine does not crank)
Power sup-
ply
Input from
alternator
generation
Starting
input to
starting
motor
Starting out-
put to start-
ing motor
Power sup-
ply
Starting
input to
starting
motor
Input from
alternator
generation
Resistance
PC200, 200LC, 220, 220LC-8M0
Voltage 20 to 30 V
Voltage Max. 1 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Max. 1 V
Max. 1 z
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage Max. 1 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V
Voltage 20 to 30 V