4. Service procedures
4)Symptom: LCD on the remote controller is displaying “CHECK E04”. (Unusual communication between the indoor and outdoor units.)
Start
Cut the breaker and remove the indoor/outdoor unit control lines connected to U1 and U2 of the indoor unit 8P terminal plate. After shorting the test pin (CN2) on the indoor unit PCB, switch the breaker on. Does the LED (red) on the PCB light up?
Yes
No
Is the contact good at the 2P connector for indoor serial communications on the outdoor unit PCB?
Yes
Replace the indoor unit PCB.
No
Correct the connections.
Section
1
Cut the breaker, remove the indoor/outdoor unit control lines connected to U1 and U2 of the outdoor unit 8P terminal plate. After shorting the test pin (CN11) on the outdoor unit PCB, switch the breaker on. Do the LEDs (red, × 2) on the PCB flash?
Yes
No
Is the contact good at the 2P connector for indoor serial communications on the outdoor unit PCB?
No
Correct the connections.
2
Indoor/outdoor unit | Replace the indoor unit PCB. |
control lines are cut off
Correct the wiring.
3
0335_M_I
5)Symptom: LCD on the remote controller is displaying “CHECK E05”. (Unusual communication between the indoor and outdoor units)
Start
Indoor unit PCB transmission/ reception circuit defect
Replace the indoor unit PCB.
0336_M_I
4
SM830076
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