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33
7. Communication malfunction (E6)
Main detection points:
S
Check if the wire is damaged or the polarity is mixed between terminals.
S
Is the communication circuit of the indoor mainboard damaged?
S
Is the communication circuit of the outdoor mainboard (AP1) damaged?
Malfunction diagnosis process:
E6
Did the unit operate normally
before malfunction?
Is the polarity correct
between all terminals?
If the wiring is
damaged?
Replace the
wire
Check the malfunction
type with communication
malfunction detector
Malfunction of outdoor
communication circuit
Replace outdoor
mainboard AP1
Replace indoor
mainboard AP2
Is the malfunction
eliminated?
Is the malfunction
eliminated?
End
Check the connection
wire according to the
wiring diagram.
Reconnect the wire or
replace the connection
wire according to the
wiring diagram.
Is the malfunction
eliminated?
If the connection wire
is connected well?
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
Fig. 36 – Troubleshooting
Summary of Contents for 38GRQB09-3
Page 10: ...10 Outdoor unit Fig 11 Sizes 09 12...
Page 46: ...46 EXPLODED VIEW AND PARTS LIST Indoor Unit Fig 47 Indoor Unit...
Page 48: ...48 OUTDOOR UNIT Fig 48 Outdoor Unit...
Page 50: ...50 Fig 49...
Page 53: ...53 Shut off power hold both ends of horizontal...
Page 54: ...54...
Page 55: ...55...
Page 56: ...56 ziptie side cutters...
Page 57: ...57...
Page 58: ...58...
Page 59: ...59...
Page 60: ...60...
Page 73: ...73 6 7 8...
Page 74: ...74 9 Remove electric box 10 Remove evaporator...
Page 75: ...75...
Page 76: ...76 11 Remove swing blade...
Page 77: ...77 12 Remove cross flow blade and motor...
Page 78: ...78 13 Remove drive box...
Page 90: ...90 APPENDIX Appendix 1 Reference Sheet of Celsius and Fahrenheit...
Page 95: ...95 UNIT BREAKDOWNS a b c d e...
Page 96: ...96 f g h...
Page 97: ...97...
Page 98: ...98...
Page 99: ...99...