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38MGR-04SM Specifications subject to change without notice.
41
DIAGNOSIS AND SOLUTION (CONT)
Communication malfunction between IPM board and outdoor main board) error diagnosis (E3)
Troubleshooting
ERROR CODE
E3
MALFUNCTION DECISION
CONDITIONS
PCB main chip does not receive feedback from IPM module during 60 seconds.
SUPPOSED CAUSES
• Wiring mistake
• PCB faulty
Communication malfunction between
IPM board and outdoor main board.
Is there at least one LED in
the IPM board that is illuminated?
Check the signal wire between
the IPM module and the main
board. Is it connected well?
Reconnect and retry.
Does the error still appear?
Replace the IPM board, and
check if the system runs normally.
Replace the electric
control box.
No
No
No
No
Yes
Problem solved.
No
Yes
Replace the outdoor main
board, and then check if the
system can run normally.
No
Yes
Yes