Daikin Air Conditioner 5MXS48TVJU

Pre-check for short circuit in the main circuit

Measure the voltage according to the model drawing

Ensure the voltage between DC + and DC – is 50 V or less

Ensure firm contact between multimeter probes and test points

Disconnect the connector of thermistor ASSY from the PCB

Disconnect the PCB from other PCB/parts if thermistor is soldered

Measure the resistance of thermistor 1 using multimeter

Measure the resistance of thermistor 2 using multimeter

Measure the resistance of thermistor 3 using multimeter

Does the resistance of thermistor 1 match the specified value?

Describe any abnormal stops observed

Install an inverter analyzer instead of a compressor

Ensure charged voltage of the built-in smoothing electrolytic capacitor is 10 VDC or below

Describe the connection method if terminals are not FASTON

Activate the power transistor test operation from the outdoor unit

Measure the power supply waveform between No. 1 and No. 2 on the terminal strip

Is the power supply waveform a sine wave?

Is there waveform disturbance near the zero-cross?

Verify EV connector insertion and matching

Turn the power off and on again

Do all EVs generate a latching sound?

List EVs not generating a latching sound

Disconnect the connector of the EV not generating sound

Check continuity using a multimeter between pins 5-1, 5-2, 5-3, 5-4