U8 Malfunction - Vivax ACP-12CH35GEK Service Manual

"U8" is
displayed on
the unit.
Re-energize 1
minute after
de-erergization
Is"U8"
No
still displayed?
Yes
The zero-cross detection
circuit of the mainboard is
defined abnormal. Replace
the mainboard.
M alfunction is
eliminated.
The unit returns to normal.
Conclusion: U8 is displayed due to
instant energization after de-
energization while the capacitor
discharges slowly.