Mitsubishi Electric PLA Sseries Service Manual page 28

9-6. HOW TO CHECK THE PARTS
Parts name
Room temperature
Measure the resistance with a multimeter.
thermistor (TH1) (Parts temperature 10 to 30°C)
Pipe temperature
thermistor/liquid (TH2)
Condenser/evaporator
Refer to "9-6-1 Thermistor".
temperature thermistor (TH5)
Vane motor (MV) Measure the resistance between the terminals with a multimeter.
(At the ambient temperature 20 to 30°C)
White
M
Orange
Red
Yellow
Blue
Drain pump (DP)
1 Check if the drain float switch works properly.
2 Check if the drain pump works and drains water properly in cooling operation.
1 Red
3 If no water drains, confirm that the check code P5 will not be displayed 10 minutes after the
Purple
2
Black
3
Note: The drain pump for this model is driven by the internal DC motor of controller board, so it is not
Normal
Red–Black: Input 13 V DC → The motor starts to rotate.
Purple–Black: Abnormal (check code P5) if it outputs 0–13 V square wave (5 pulses/rotation),
Drain float switch (FS)
Measure the resistance between the terminals with a multimeter.
Moving part
1
2
3
4
i-see Sensor (Option)
1 2 3 4
1 2 3 4
i-see Sensor motor
Measure the resistance between the terminals with a multimeter.
(Option)
(At the ambient temperature 20 to 30°C)
White
M
Orange
Red
Blue Yellow
OCH783
Normal
4.3 to 9.6 k"
Connector
Red–Yellow (5–3, 0–8, 5–3, )–8)
Red–Blue (5–1, 0–6, 5–1, )–6)
Red–Orange (5–4, 0–9, 5–4, )–9)
Red–White (5–2, 0–7, 5–2, )–7)
operation starts.
possible to measure the resistance between the terminals.
and the number of rotation is not normal.
State of moving part Normal
UP Short
DOWN Open
Turn the power ON while the i-see Sensor connector is connected to the CN4Z on indoor
controller board. A communication between the indoor controller board and i-see Sensor
board is made to detect the connection.
Normal: When the operation starts, the motor for i-see Sensor is driven to rotate the i-see Sensor.
Abnormal: The motor for i-see Sensor is not driven when the operation starts.
Note: The voltage between the terminals cannot be measured accurately since it is pulse output.
Normal
Red–Yellow Red–Blue
250 "
Check method and criterion
Abnormal
Opened or short-circuited
Normal
300 "
Abnormal
Other than short
Other than open
Red–Orange Red–White
28
Abnormal
Open or short
Switch
Magnet
Moving
Part
Abnormal
Open or short