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40MPHA-03SM Specifications subject to change without notice.
37
E4/E5/F1/F2/F3 (Open circuit or short circuit of temperature sensor diagnosis and solution)
Description:
If the sampling voltage is lower than 0.06V or higher than 4.94V, the LED displays the failure.
Recommended parts to prepare:
• Wiring mistake
• Faulty sensor
• Faulty PCB
Troubleshooting and Repair:
Fig. 23 —Multimeter
Check the connection between
temperature sensor and PCB.
Replace indoor or outdoor PCB.
Is it within acceptable
parameters?
Is it properly wired ?
Ensure proper connections .
NO
Measure the resistance value
of the sensor.
YES
Replace the sensor.
NO
YES