YES
NO
The unit returns to normal.
Conclusion:U8 is displayed due
to power off/on while the
capacitor discharges slowly.
4. Malfunction of Zero-crossing Inspection Circuit Malfunction of the IDU Fan Motor U8
Main detection points:
• Instant energization after de-energization while the capacitor discharges slowly?
• Is the zero-cross detection circuit of the mainboard defined abnormal?
Malfunction diagnosis process:
End
Turn power off for 1 minute,the turn
back on
U8 is still displayed
The zero-cross detection circuit of
the mainboard is defined abnormal.
Replace the mainboard with the
same model
Start
