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Error code reference
Haier Air Conditioner Error Code E12
Broken CT wire - possible damaged control board, short gas, poor 4-way valve switch (Power blinking, Timing OFF, Running blinking)
SourceHaier HSU-22H03/R2 - Full Service Manual: Split AC Unitp. 37
Diagnostic procedure
The full E12 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
1
First diagnostic step
Check CT wire connections, control board, refrigerant charge, and 4-way valve
SourceHaier HSU-22H03/R2 - Full Service Manual: Split AC Unitp. 37
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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Where this code is documented
1 manual in the MyPros+ library documents this code for Haier air conditioner.
Models covered by the manuals that document this code
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