Carrier 40MPHA Service Manual page 33

DIAGNOSIS AND SOLUTION (CONT)
Eb (Communication error between the Indoor PCB and Display Board)
Description: Indoor PCB does not receive feedback from the display board.
Recommended parts to prepare:
S
Wiring mistake
S
PCB faulty
S
Display board malfunction
Troubleshooting and Repair:
Power off , then restart the
unit 2 minutes later.
Is it still displaying
the error code ?
Check the wirings and
Replace the indoor main PCB
Is the problem solved?
The unit operates normally
YES
connection.
Is it normal ?
YES
YES
NO The unit operates normally
Correct the connection
NO
or replace the wirings
NO Replace the display board
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