Daikin AT12BV1LS Pocket Manual page 96

Si10-417
5.2.35 Thermistor or Related Abnormality
(Outdoor Unit)
Remote
Controller
Display
Outdoor
Unit LED
Display
Method of
Malfunction
Detection
Malfunction
Decision
Conditions
Supposed
Causes
Service Diagnosis
P4, J3, J6, J8, J9, H9
A 5 1 4 2
This type of error is detected by checking the thermistor
input voltage to the microcomputer.
[A thermistor error is detected by checking the
temperature being detected by each thermistor.]
When the thermistor input is above 4.96 V or below 0.04
V with the power on, the J3 error is judged if the
discharge pipe thermistor temperature is smaller than
the condenser thermistor temperature, or the system will
be shut down if all the units are judged with the J8 error.
Connector in poor contact
Thermistor defective
Outdoor unit PCB defective
Indoor unit PCB defective
Condenser thermistor defective in the case of J3 error
(outdoor unit heat exchanger thermistor in the cooling
mode, or indoor unit heat exchanger thermistor in the
heating mode)
4 3 1 4 1
Troubleshooting
95