37MGRA EL 01 (Indoor and Outdoor Unit Communication Error Diagnosis and Solution)

Diagnostic codes covered

EL 01(EL01)

• EL 01 – IDU and ODU Communication Error

Description: Indoor unit can not communicate with outdoor unit. Recommended parts to prepare: Signal Wires, Magnetic Ring, Indoor PCB, Outdoor PCB Troubleshooting and repair: Troubleshooting for Current Loop Communication Loss : Start: Power off , then Power on the A/C by the Breaker. (Reconnect the power wire). Is it still displaying the error code? Yes Check wiring on the outdoor and indoor terminal follow the wiring diagram. Is all No connecting correctly? Reconnect the wiring No No Yes Turn on the indoor unit by remote. Does the indoor unit display? No Measure Vs, is it moving alternately between positive value and negative value? (Vs is the No voltage between S and L2). A: Is all the wiring between terminal and Indoor PCB connect ok? Yes Yes Yes Yes Turn off the all indoor units. Is IPM power LED or operating LED lamp on ? Yes Power on by remote controller. Is it still displaying the error code after 3 minutes? Is main board lamp on? Is the reactor connecting well Yes No Yes Is indoor unit’s number correct? Check on the outdoor check point. The number displayed in check point inquiry refers to the quantity of units with a working connection. Trouble is solved No first time No second time