MXZ-5C42NA3 Service Manual

113
NOTE: Blinking patterns of this mode di󰀨er from the ones of
TROUBLESHOOTING CHECK TABLE (12-4.).
The left lamp of
OPERATION
INDICATOR lamp
(Indoor unit)
Abnormal point
(Failure mode/protection)
LED indication
(Outdoor P.C.
board)
Condition Remedy
Indoor/outdoor
unit failure
mode recall
function
LED 1 LED 2
8-time blink Outdoor fan motor Lit Lit A failure occurs 3 consecutive times within
30 seconds after the fan gets started.
• Refer to 12-6. "Check of outdoor
fan motor".
—
4-way valve switching operation
abnormality.
Lit
12 times Connector of R.V. coil is disconnected,
poorly connected or 4-way valve is faulty.
• Refer to 12-6. "Check of R.V. coil".
• Check the 4-way valve.
○
9-time blink Outdoor control system Lit 5 times Nonvolatile memory data cannot be read
properly.
• Replace the outdoor control P.C.
board.
○
10-time blink Low discharge temperature
protection
Lit Lit The frequency of the compressor is kept
80 Hz or more and the discharge tempera-
ture is kept under 102.2°F for more than
20 minutes.
• Check refrigerant circuit and refrig-
erant amount.
• Refer to 12-6. "Check of LEV".
—
11-time blink Communication error
between P.C. boards
Lit 6 times
Communication error occurs between the
outdoor control P.C. board and outdoor
power P.C. board for more than 10 seconds.
• Check the connecting wire between
outdoor control P.C. board and out-
door power P.C. board.
—
The communication between boards protec-
tion cut-out operates 2 consecutive times.
○
Current sensor Lit 7 times A short or open circuit is detected in the cur-
rent sensor during compressor operating.
—
—
Current sensor protection cut-out operates
2 consecutive times.
○
Zero cross detecting circuit 5 times Not lit Zero cross signal cannot be detected while
the compressor is operating.
• Check the connecting wire among
outdoor control P.C. board and out-
door power P.C. board.
—
The protection cut-out of the zero cross
detecting circuit operates 10 consecutive
times.
○
Converter 5 times Not lit A failure is detected in the operation of the
converter during operation.
• Check the voltage of power supply.
• Replace the outdoor power P.C.
board.
—
Bus-bar voltage 5 times Not lit The bus-bar voltage exceeds 400 V or falls
to low level during compressor operating.
• Check the voltage of power supply.
• Replace the outdoor power P.C. board
or the outdoor control P.C. board.
14-time blink 4-way valve switching operation
abnormality.
Lit 12
times
Connector of R.V. coil is disconnected,
poorly connected or 4-way valve is faulty.
• Refer to 12-6. "Check of R.V. coil".
• Check the 4-way valve.
○
15-time blink LEV and drain pump Lit Lit The indoor unit detects an abnormality in
the LEV and drain pump.
• Refer to 12-6. "Check of LEV".
• Check the drain pump of the indoor unit.
—
OBH702M