Engine Does Not Start (Engine Does Not Rotate) - Komatsu Galeo PC800-8 Shop Manual

SEN00793-02
E-1 Engine does not start (Engine does not rotate)
Failure
• The engine does not start. (Engine does not rotate)
phenomenon
Relative
• The engine starting circuit is equipped with the start lock mechanism of lock lever type.
information
Battery capacity
1
insufficient
Defective circuit breakers
2
No. 1 or 6 or fuse 3 or 20
Defective starting switch
3
(Internal disconnection)
Defective lock switch
4
(Internal short-circuiting)
Possible causes
and standard
Defective starting motor
value in normal
5 cut-out relay
state
(Internal defect)
Defective starting motor
6
(Internal defect)
Defective alternator (Inter-
7
nal short-circuiting)
6
Cause Standard value in normalcy and references for troubleshooting
aTurn the engine starting switch OFF for the preparations, and hold it in
the OFF position during the troubleshooting.
If a circuit breaker is turned OFF or a fuse is broken, the circuit probably
has grounding fault (See cause 9).
aTurn the engine starting switch OFF for the preparations, and hold it in
the ON position and start the engine during the troubleshooting.
H06 (male)
Between (1) – (4)
aTurn the engine starting switch OFF for the preparations, and hold it in
the OFF position during the troubleshooting.
S14 (female)
Between (1) – (3)
aTurn the engine starting switch OFF for the preparations, and hold it in
the OFF position during the troubleshooting.
R06 (male), R07 (male)
aTurn the engine starting switch OFF for the preparations (with the wir-
ing harness connected), and start the engine for troubleshooting.
Between B – chassis
Between ST (1) –
chassis ground
Between ST (2) –
chassis ground
If the above voltages are normal and the starting motor does not rotate,
the starting motor has a defect in it or the engine is defective.
aTurn the engine starting switch OFF for the preparations (with only
wiring harness R disconnected), and hold it in the ON position during
the troubleshooting.
Battery voltage
Min. 24 V
Starting switch
Lock lever
LOCK
Between (1) – (2)
Between (3) – (5)
Between (3) – (6)
Starting motor
B (Power
ground supply)
S (Start)
R
(Charge)
Alternator
Between terminal R –
chassis ground
40 Troubleshooting
Electrolyte specific gravity
Min. 1.26
Resistance
OFF Min. 1 Mz
Max. 1 z
ON
Resistance
FREE Min. 1 Mz
Max. 1 z
Resistance
100 – 500 z
Min. 1 Mz
Max. 1 z
Voltage
20 – 30 V
20 – 30 V
Max. 12 V
Voltage
Max. 12 V
PC800, 850-8