Carrier 38QUS012D8S - Page 114

Troubleshooting
Electrical Control System 112
2.4.1.3. Indoor EEPROM Malfunction
Malfunction conditions
Main PCB chip does not receive feedback from EEPROM chip
Possible causes
● Installation mistakes
● Faulty PCB
Yes
Replace the indoor main PCB
Power off, then restart the
unit 2 minutes later. Does a
problem remain?
EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and
reprogrammed using a pulsed voltage.
2.4.1.4. Water-Level Alarm Malfunction
Malfunction conditions
If the sampling voltage is not 5V, the LED will display the failure
code.
Possible causes
● Wiring mistakes
● Faulty water-level switch
● Faulty water pump
● Faulty indoor PCB
Is the water-level
switch inserted
properly?
Is the water-level
switch inserted
properly?
No
Insert the water-level switch
properly
Insert the water-level switch
properly
Is the water-level
switch broken?
Is the water-level
switch broken?
Yes
Replace the water-level switch
Replace the water-level switch
Replace the water pump. Is
the malfunction still not
resolved?
Replace the water pump. Is
the malfunction still not
resolved?
Yes
No
Yes
Replace the indoor main PCB
Replace the indoor main PCB
Power off, then restart the unit 2 minutes
later. Is it still displaying the error code?
Power off, then restart the unit 2 minutes
later. Is it still displaying the error code?
Yes