![background image](http://html1.mh-extra.com/html/carrier/40mbab/40mbab_service-manual_2562112031.webp)
40MBAB: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
31
DIAGNOSIS AND SOLUTION (CONT.)
EH 0b - Communication error between the two indoor chips Diagnosis and Solution
Description: Indoor PCB main chip does not receive feedback from another chip.
Recommended parts to prepare:
• Indoor main board
• Adapter board adapter
Troubleshooting and Repair:
Yes
No
No
No
Trouble is resolved.
Yes
Shut off the power supply and
turn it on 2 minutes later.
Is it still displaying
the error code?
Yes
Yes
Check the connection wires
between the adaptor board
and the main board.
Is it connected properly?
Reconnect and retry.
Does the error still appear?
Replace the transfer board.
Is the system running normally?
Replace the indoor main board.