Mitsubishi Electric JT-SB116EH-W-CA, Handbook

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—22—
Approx. 2~14k
Ω
Disconnecting CN4 from the control circuit, measure the
resistance between pins 2 and 3 at the lead wire side.
If the normal value is not detected, replace the heater thermostat.
Error Mode Display
Defective room
thermostat
Heater switch
Defective control
circuit
Check if the heater switch is turned ON.
If no error is found after checking the above, replace the
control circuit.
If no error is found after checking the above, replace the
control circuit. Defective control
circuit
Replace the control circuit.
(Microcomputer signal error)
Defective control
circuit Replace the control circuit.
Error Mode Display
Defective heater
Defective control
circuit
Check if CN4 or CN12 is disconnected.
(CN12 is on the indicator circuit board.) Disconnected room
thermostat lead wires
Cause Check Method and Remedy
Check if CN9 is disconnected. Disconnected heater
thermostat lead wire
Disconnecting CN9 from the control circuit board, measure
the resistance between pins 2 and 3 at the lead wire side.
If the normal value is not detected, replace the heater
thermostat.
Note) If the circuit is open due to broken wires, etc., the
resistance becomes
∞
Ω
.
Defective heater
thermostat
(Room thermostat error)
Power
O
Heater
O
Check
O
Blue LED
O
(Heater error)
Power
O
Heater Check
O
Blue LED
O
Check if TAB3 or 4 is disconnected.
Disconnected heater
power supply wire
Check if specified power is output at both ends of TAB3 and
4. If not, replace the control circuit.
If no error is found after checking the above, replace the
heater.
Hot air does not blow.
Normal Value
The value shown at left applies when
the room temperature is 0~40°C.
Normal Value
Approx. 150k
Ω
or over
Check the value shown at left while the
heater is cold (not higher than 100°C).
Troubles related to the heater
Power
O
Heater
O
Check Blue LED
O
(Microcomputer error)
Defective control
circuit
Power
O
Heater
O
Check Blue LED
O
Cause Check Method and Remedy