IVT AE-X12GR-N Service Manual page 37

Status of Indication Malfunction
indoor/ by LED1 No. dis-
outdoor on out- played on
units door unit main unit
*2 display sec-
tion *1
Main
cate-
gory
Indoor 17
unit in
operation
Outdoor
unit in
complete
shutdown
18
Indoor/ 19
outdoor
units in
complete
shutdown
Indoor/ 20
outdoor
units in
operation
Indoor/ 88
outdoor
units in
operation
Malfunction indications due to erroneous wiring during air conditioner installation
Inter-unit wiring error mode
1
1 1
Indoor Outdoor
N N
unit
2 2
Content of diagnosis
Sub- Main category
cate-
gory
-0 Wires between Serial open-circuit
units
Outdoor unit does
not turn on due to
erroneous wiring
-0 Serial short-circuit
-1 Serial erroneous wir-
ing
-0 Indoor unit fan Indoor unit fan error
-0 Indoor unit con- EEPROM data error
trol PCB
Control and dis- Communication
play PCB error
Indoor unit relay
Malfunction diagnosis display
unit
Inspection location/method
Sub-category
(1) Check the wires between
units.
(2) Check voltage between
Nos. 1 and 2 on the
indoor/outdoor unit termi-
nal boards.
(1) Check the wires between
units.
(2) Check the outdoor unit
fuse.
(3) Check 15-V, 13-V and 5-V
voltages on the PWB.
Check resistance between
IPM terminals.
(4) Check pins No. 5 and 7 of
connector CN3 of the out-
door unit fan motor for
short-circuit.
(5) Outdoor unit control PCB
(1) Check the wires between
units.
(1) Check the wires between
units.
(1) Check the indoor fan
motor for proper rotating
operation.(Check fan
lock.)
(2) Check the lead wire of the
indoor fan motor for open-
circuit.
(3) Check CN1 of the indoor
unit fan motor for secure
installation.
(4) No abnormality found in
above inspections (1)
through (3).
(EEPROM read data
error)
(1) Check for disconnected
connector between control
PCB and display PCB,
and open-circuit in lead
wires.
(2) Check that control PCB
outputs signals correctly.
Symptom
Turns On momentarily, then turns Off.
"18-1"
3 – 17
AEX12GRN
Remedy
(1) Connect stable power
supply.
(2) Replace the outdoor
unit control PCB
assembly.
(1) Correct the wiring.
(2) Replace the fuse/out-
door unit control PCB
assembly.
(3) Replace the outdoor
unit control PCB
assembly.
(4) Replace the outdoor
unit fan motor.
(5) Replace the outdoor
unit control PCB
board.
(1) Correct the wiring.
(1) Correct the wiring.
(1) Replace the indoor
fan motor.
(2) Replace the indoor
fan motor.
(3) Correct the installation
of CN1 of the indoor
fan motor.
(4) Replace the indoor
unit control PWB.
Replace the indoor
unit control PWB.
(1) Insert connectors cor-
rectly, or replace con-
trol PWB.
(2) Replace control PWB.