Carrier 40MBDAQ - Page 40

40MBDAQ: Service Manual
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40
DIAGNOSIS AND SOLUTION (CONT.)
J4 (Communication error between outdoor main chip and compressor driven chip)
Description: The main PCB has not received feedback from the driven chip for one minute or the feedback data is incorrect.
The driven chip has not received feedback from the main PCB for one minute or the feedback data is wrong. The failure code
disappears after the compressor stops or the communication returns to normal.
Recommended parts to prepare:
• Outdoor PCB
• Compressor driven chip
• The signal wire
Troubleshooting
Communication error between the outdoor
main chip and compressor driven chip
Is there at least one
LED in the compressor driven
chip light?
Check the signal wire between the
compressor driven chip and the main board.
NO
Is it connected
properly?
Reconnect and retry.
NO
Does the error still appear?
Replace the
compressor driven chip.
NO
Is the system
running normally?
Replace the outdoor main board.
NO
Is the system
running normally?
Replace the electric control box.
NO
Problem is resolved.
YES
YES
NO
YES
YES