Friedrich MRM09Y1J, Service & Parts Manual

Page: 91 / 135

91 PB
TROUBLESHOOTING
Diagnostic Codes
No. Malfunction
Name
Display Method of Indoor Unit Display Method of Outdoor Unit A/C status Possible Causes
Dual-8
Code
Display
Indicator Display (During blinking,
ON 0.5s and OFF 0.5s) Indicator has 3 kinds of display
status and during blinking, ON
0.5s and OFF 0.5s
Power
Indicator Cool
Indica -
tor
Heating
Indicator Yellow
Indicator Red Indi-
cator
Green
Indicator
53 normal
communi -
cation
OFF 0.5s
and blink
once
54 defrosting H1 OFF
3s and
blink
once
(during
blinking,
ON 10S
AND
OFF
0.5S
OFF 1s
and blink
twice
Defrosting will occur in
heating
mode. Compressor will
operate
while indoor fan will stop
operation.
Its the normal state
55 malfunc -
tion of
zero-cross
detection
circuit
U8 The Complete Unit
Stops
1. Power supply is
abnormal
2. Detection circuit of
indoor control main -
board is abnormal.
56 Malfunc -
tion of
detect -
ing plate
(WIFI)
JF