Error code reference

Daikin Air Conditioner Error Code A0

Error of external protection device - open or short circuit detected between external input terminals in indoor unit.

SourceDaikin Air Conditioner - Service Manual: RZR-P, RZQ-P(9) Seriesp. 109

Daikin codes Daikin air conditioner codes

Diagnostic procedure

The full A0 procedure

Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.

MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Check if external protection device is connected to terminals T1 and T2 of the indoor unit terminal block.

SourceDaikin Air Conditioner - Service Manual: RZR-P, RZQ-P(9) Seriesp. 109

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More steps, wiring diagram references, and verified part numbers

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Where this code is documented

1 manual in the MyPros+ library documents this code for Daikin air conditioner.

Models covered by the manuals that document this code

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The full A0 procedure

Where this code is documented

Models covered by the manuals that document this code

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