Air Conditioner Does Not Operate - Komatsu ecot3 PC300LC-8 Shop Manual

SEN02632-02
E-29 Air conditioner does not operate
Trouble • Air conditioner does not start.
Related infor- • For electrical circuit inside the air conditioner unit, refer to the structure, function and maintenance
mation standard, "Air conditioner system."
1 Defective fuse No. 11
Defective A/C Hi/Lo pressure
switch
2
(Internal disconnection or
defective contact)
Disconnection in wiring har-
ness
3 (Disconnection in wiring or
defective contact in connec-
Possible causes
tor)
and standard
value in normal
state
Ground fault in wiring har-
ness
4
(Short circuit with GND cir-
cuit)
5 Defective air conditioner unit
60
Cause Standard value in normal state/Remarks on troubleshooting
If fuse is burnt, circuit probably has ground fault.
a
a
Wiring harness between F01-11 outlet –
AC01 (male) (4)
Wiring harness between M26 (male) (7) –
P17 (female) (1)
Wiring harness between AC01 (male) (5) –
chassis ground
Wiring harness between P17 (female) (2) –
J04 – chassis ground
a
Wiring harness between F01-11 outlet –
AC01 (male) (4) and chassis ground
Wiring harness between AC01 (male) (7) –
P17 (female) (1) and chassis ground
a
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
P17 (male)
Between (1) – (2)
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
(The table indicates internal defect of an air conditioner)
AC01
Between (1) – (3)
40 Troubleshooting
1
Resistance
Max. 1 z
Resis-
Max. 1 z
tance
Resis-
Max. 1 z
tance
Resis-
Max. 1 z
tance
Resis-
Max. 1 z
tance
Resis-
Min. 1 Mz
tance
Resis-
Min. 1 Mz
tance
Voltage
20 – 30 V
PC300, 350-8