Haier HSU-12LEK03-Y2 Service Manual page 38

Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector,
Whether terminal CN6 on
indoor PCB contact wellt?
YES
Pull the sensor out of the mainboard
1) Measure the value of resistance Between its two
jumpers
2) Measure the temperature at the room temperature
sensing head.
Check the value of the
sensor to see whether the
sensor is damaged or not?
NO
The indoor PCB is broken, replace with new indoor PCB
notes:
E1: Room temperature sensor failure
E2: Indoor heat-exchange sensor failure
7.2.2 Indoor EEPROM error
E 4
E 4
E 4
Indoor Display
Method of The date received from EEPROM is checked whether normal
Malfunction
Detection
Malfunction
When the date sent from EEPROM cannot be received normally , or when EEPROM is not
Decision detected
Conditions
Supposed
Faulty PCB
Causes
Troubleshooting
Replace the PCB of indoor unit
HSU-12LEK03-Y2
else parts damage may be occurred.
NO
YES
35
Codes and description
Pull out the terminals on the indoor mainboard and
reinsert them
Correct the connection
Sensor is broken,replace it with new sensor
Domestic air conditioner
or