Carrier 40MAHBQ36XA3 - Temperature Sensor Circuit Diagnosis and Solution (E4;E5;F1;F2;F3)

SG-40MAHB-01: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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DIAGNOSIS AND SOLUTION (CONT)
Open circuit or short circuit of temperature sensor diagnosis and solution (E4/E5/F1/F2/F3)
Malfunction Decision Conditions
If the sampling voltage is lower than 0.06V or higher than 4.94V, the LED displays the failure.
Possible Causes:
• Wiring mistake
• Sensor faulty
• PCB faulty
Troubleshooting
Fig. 26 — Check the connection
Check the connection
between the temperature
sensor and PCB.
Correct the connection.No
Yes
Replace the indoor or outdoor
main PCB.
Measure the resistance
value of the sensor.
Replace the sensor.No
Yes