Carrier 42QFD048D8S Service Manual page 102

TS07: Indoor PCB / Display board communication error diagnosis and solution
Description: Indoor PCB does not receive feedback from the display board.
Recommended parts to prepare:
• Communication wire
• Indoor PCB
• Display board
Troubleshooting and
Power off, then restart the unit 2 minutes
repair:
later
Is it still displaying the error code?
YES
Check the wirings and connections
Are all the connections
good?
YES
Replace the indoor main PCB
Does the error still exist?
Replace the display board

The unit functions normally
NO
Ensure a proper connection
NO
Troubleshooting 