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40MBAB: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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DIAGNOSIS AND SOLUTION (CONT.)
EL 16 - Communication malfunction between adapter board and outdoor main board Diagnosis and
Solution
Description: The adapter PCB cannot detect the main control board.
Recommended parts to prepare:
• Connection wires
• Adapter board
• Outdoor main PCB
Troubleshooting and Repair:
DIAGNOSIS AND SOLUTION (CONT.)
FL 09 - Indoor and outdoor mismatch malfunction Diagnosis and Solution
Description: Indoor and outdoor units are mismatched, the LED displays this code. Replace the matching indoor or outdoor
unit.
YES
Power off, then restart the unit after 3 minutes.
Does the error still exist?
Replace the outdoor
main control board.
Does a problem remain?
The unit is operating normally.
NO
Check the wirings and connections.
YES
Are all the connections
good?
Ensure proper connections.
NO
YES
Replace the adapter main PCB.
The problem is solved.
NO