AYZP40KR
3 – 6
[5] GENERAL TROUBLESHOOTING CHART
1. Indoor unit does not turn on
2. Indoor unit fan does not operate
3. Indoor unit fan speed does not change
4. Remote control signal is not received
5. Louvers do not move
6. There is noise in TV/radio
Main cause
Inspection method
Normal value/condition
Remedy
Cracked PWB.
(Cracked pattern)
Check visually.
There should be no cracking in
PWB or pattern.
Replace PWB.
Open-circuit in FU1 (250 V, 2.5A). Check melting of FU1.
There should be no open-circuit.
Replace PWB.
Main cause
Inspection method
Normal value/condition
Remedy
Open-circuit in heat exchanger
thermistor (TH2) (in heating oper-
ation)
Measure thermistor resistance
(dismount for check).
Refer to THERMISTOR TEPER-
ATURE CHARACTERISTICS-1
Replace thermistor.
There should be no open-circuit
or faulty contact.
Replace thermistor.
Disconnected heat exchanger
thermistor (TH2) (in heating oper-
ation)
Inspect connector on PWB.
Check thermistor installation con-
dition.
Thermistor should not be discon-
nected.
Install correctly.
Main cause
Inspection method
Normal value/condition
Remedy
Remote control not designed to
allow fan speed change.
Check operation mode.
Fan speed should change except
during dehumidifying operation,
ventilation, light dehumidifying
operation, internally normal oper-
ation
Explain to user.
Main cause
Inspection method
Normal value/condition
Remedy
Batteries at end of service life.
Measure battery voltage.
2.5 V or higher (two batteries in
series connection)
Install new batteries.
Batteries installed incorrectly.
Check battery direction.
As indicated on battery compart-
ment.
Install batteries in indicated direc-
tion.
Lighting fixture is too close, or flu-
orescent lamp is burning out.
Turn off light and check.
Signal should be received when
light is turned off.
Change light position or install
new fluorescent lamp.
Use Sevick light (Hitachi).
Check if Sevick light (Hitachi) is
used.
Signal may not be received
sometimes due to effect of Sevick
light.
Replace light or change position.
Operating position/angle is inap-
propriate.
Operate within range specified in
manual.
Signal should be received within
range specified in manual.
Explain appropriate handling to
user.
Open-circuit or short-circuit in wir-
ing of light receiving section.
Check if wires of light receiving
section are caught.
Wires of light receiving section
should not have any damage
caused by pinching.
Replace wires of light receiving
section.
Defective light receiving unit.
Check signal receiving circuit
(measure voltage between termi-
nals 7 and 8 of connector CN7).
Tester indicator should move
when signal is received.
Replace PWB.
Dew condensation on light receiv-
ing unit.
Check for water and rust.
Signal should be received within
range specified in manual.
Take moisture-proof measure for
lead wire outlet of light receiving
section.
Main cause
Inspection method
Normal value/condition
Remedy
Caught in sliding section.
Operate to see if louvers are
caught in place.
Louvers should operate smoothly. Remove or correct catching sec-
tion.
Disconnected connector (CN3,
CN4 on relay PWB, louver motor
side)
Inspect connectors.
Connectors or pins should not be
disconnected.
Install correctly.
Contact of solder on PWB
(connector section on PWB)
Check visually.
There should not be solder con-
tact.
Correct contacting section.
Main cause
Inspection method
Normal value/condition
Remedy
Grounding wires not connected
properly.
Check grounding wire connec-
tions.
Grounding wires should be con-
nected properly.
Connect grounding wires prop-
erly.
