Carrier 42QHF012DS Service Manual page 65

12.3.2 For the outdoor unit
12.3.2 1 Outdoor EEPROM malfunction(ODU E0)
Outdoor EEPROM malfunction
Yes
If the EEPROM chip
is welded on PCB,
replace the PCB
directly. Otherwise,
check whether the
EEPROM chip
plugged in PCB well?
Yes
Replace the outdoor main board
EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and
reprogrammed using a pulsed voltage.
12.3.2.2 Communication malfunction between IPM board and outdoor main board(ODU E3)
No Insert the EEPROM well
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