Error Code: EL 01 – Indoor & Outdoor Unit Communication Error
Applies to LETO and AURA Series
What this means:
The indoor unit is unable to communicate with the outdoor unit. This is often due to a wiring issue, a power-related fault, or a failure in one of the control boards. It may also be caused by a short-circuited component.
Try this first (easy fix):
Turn off power to your mini split completely.
Wait 2 full minutes to allow the system to reset.
Turn the power back on and check the display.
If the error is gone — you're all set.
If the error is still there — proceed to check wiring or call a technician.
What to check next (for advanced users or technicians):
Verify the wiring between the indoor and outdoor units (terminals 1, 2, and 3 must match and be firmly connected on both ends).
Measure DC voltage between the communication terminals (e.g., S and N).
Check for short circuits by unplugging components one by one (e.g., 4-way valve, heater, AC fan).
If your unit has both a main PCB and IPM board, both may need to be tested.
Faulty components or boards should be replaced.
What you might need:
Replacement indoor PCB
Replacement outdoor PCB
IPM board or short-circuited component (in some cases)
Helpful tip:
This error is commonly caused by loose or mismatched wires or a failed communication signal. If you're not comfortable using a multimeter or working with wiring, it's best to contact a professional technician.
Click here to view the detailed guide. TS02-S-INV
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