Midea M2OD-14HFN1-Q Service Manual page 51

10.3.2.2 Communication malfunction between IPM board and outdoor main board(ODU E3)
E3 display
Communication malfunction between
IPM board and outdoor main board
Is there at least one LED in
the IPM board light?
No
Check the signal wire between
the IPM board and the main
board, is it connected good?
No
Reconnect and retry. Is
error still display?
No
Replace IPM board, and
then check whether the
system can run normally
No
Replace outdoor main
board, and then check
whether the system can run
normally
No
Replace the electric control
box
Yes
Yes
Yes
Yes
Trouble is solved
No