- HVAC
- Air conditioner
PC01
Midea air conditioner error PC01: high or low voltage fault
Risk level
High
Professional inspection is recommended.
Urgency
High
Quick answer
Error code PC01 (or PC 01) on a Midea inverter split air conditioner indicates that over-voltage or low-voltage protection tripped in the voltage detection circuit. Wait 10 minutes, perform a breaker reset once household power is stable, and contact an authorized service technician if it persists.
Safety first
Stop and check this first
- Lethal high DC voltage hazard inside the outdoor electronic control box: The DC bus between terminals P and N carries 310 V to 400 V DC: never open the outdoor electrical cover yourself, and ensure the technician waits at least 10 minutes after power-off.
- Never run the air conditioner on extension cords or shared multi-outlet adapters: Midea manuals require a dedicated branch circuit with proper wire gauge and breaker sizing; extension cords cause severe voltage drops and overheating.
Safe checks you can perform
- Check for household power fluctuations or storms and wait 10 minutes
- Perform a full power reset at the dedicated circuit breaker
- Note the PC01 display and the pattern of 2 Operation flashes with Timer flashing
Leave these tasks to a qualified professional
- Do not attempt this professional task: Measure incoming AC supply voltage and inspect all power and interconnecting wires
- Do not attempt this professional task: Measure the DC bus voltage between terminals P and N in standby and at startup
- Do not attempt this professional task: Inspect the reactor and replace the IPM board, reactor, or outdoor PCB as needed
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Measure incoming AC supply voltage and inspect all power and interconnecting wires
What they doMidea's PC 01 troubleshooting guide directs the technician to verify that the AC power supply is in working order and inspect all terminal connections and wiring.
They must show youthe live AC supply voltage reading at the terminal block and the tightness and condition of the power and communication leads.
In writingthe measured AC line voltage under standby and load, noting any loose terminal repaired or whether a voltage regulator is required.
Measure the DC bus voltage between terminals P and N in standby and at startup
What they doMidea's PC 01 flowchart specifies powering on the unit and measuring DC voltage between P and N on the outdoor board: around 310 V, 340 V, or 380 V DC in standby, and 220 V~400 V when starting.
They must show youthe multimeter DC voltage measurements across terminals P and N during both standby and compressor startup.
In writingthe recorded P-N DC bus voltages in standby (310 V, 340 V, or 380 V DC) and startup (220 V~400 V) used to isolate the fault.
Inspect the reactor and replace the IPM board, reactor, or outdoor PCB as needed
What they doFollowing the Midea PC 01 diagnostic tree, the technician must check the reactor wiring and continuity and replace the faulty reactor, IPM board, or outdoor electric control box.
They must show youthe condition and continuity test of the reactor and the replaced outdoor control component.
In writingthe reactor test result and the exact part replaced (reactor, IPM board, or outdoor main PCB).
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Check for household power fluctuations or storms and wait 10 minutes
- Who:
- Homeowner checking household power without tools
- How:
- Notice whether lights or other appliances in your home are flickering and wait about 10 minutes as recommended in the Midea owner's manual so line voltage can stabilize; switch off the breaker during severe swings.
- Result that matters:
- Determine whether PC01 was triggered by an external utility voltage disturbance
- If the PC01 code clears automatically once household power stabilizes and the air conditioner resumes normal operation, monitor the unit
- If household power is steady but PC01 remains on the indoor display, proceed with a full power reset at the breaker
- Evidence to keep:
- Note of the time of the fault and any utility brownouts or storms in your area
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
Perform a full power reset at the dedicated circuit breaker
- Who:
- Equipment owner at the electrical panel
- How:
- Turn the air conditioner off with the remote, switch off its circuit breaker for a few minutes, restore power, and turn the unit back on.
- Result that matters:
- Check whether the voltage protection circuit resets under stable supply power
- If the system starts cooling or heating normally without displaying PC01 or flashing the Operation and Timer lamps, continue normal use
- If PC01 returns as soon as the outdoor unit attempts to start, disconnect power and call an authorized service center
- Evidence to keep:
- Note of whether PC01 appears immediately in standby or only when the outdoor compressor tries to start
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
Note the PC01 display and the pattern of 2 Operation flashes with Timer flashing
- Who:
- Equipment owner observing the indoor display panel
- How:
- Before switching off the breaker, confirm whether the display reads PC01 (or PC 01) and whether the Operation lamp flashes 2 times while the Timer lamp flashes continuously.
- Result that matters:
- Record the exact voltage-protection indicator pattern for the technician
- If you have noted the exact PC01 code and indicator light pattern, share both details with the authorized technician
- If you smell burning insulation or see arcing at the disconnect switch or outdoor unit, leave the circuit breaker off immediately
- Evidence to keep:
- Photo or short video of the PC01 display and the Operation and Timer lamp flash pattern
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- HVAC
- Brand
- Midea
- Product type
- Air conditioner
Known code variants
- error PC 01 Midea
- error PC01 Midea
- Midea error PC 01
- Midea error PC01
- Midea PC 01
- Midea PC01
- over voltage or low voltage protection PC01 Midea
- PC 01
- PC01
- protección de voltaje Midea PC01
What it means
According to the Midea US ductless split installation manual (Table 9), the Midea US owner's manual, the Midea Mexico MAS12C2AGV32 R32 manual, and Midea's official PC 01 domestic troubleshooting guide, indoor display code PC01 or PC 01 (accompanied by 2 flashes of the Operation lamp and a flashing Timer lamp) means abnormal voltage increases or drops were detected by the voltage detection circuit. Other Midea inverter series may vary, and the PC01 code on its own never proves that an electronic control board has failed.
Warnings and stop conditions
- Highsource verified
Lethal high DC voltage hazard inside the outdoor electronic control box: The DC bus between terminals P and N carries 310 V to 400 V DC: never open the outdoor electrical cover yourself, and ensure the technician waits at least 10 minutes after power-off.
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
- Mediumsource verified
Never run the air conditioner on extension cords or shared multi-outlet adapters: Midea manuals require a dedicated branch circuit with proper wire gauge and breaker sizing; extension cords cause severe voltage drops and overheating.
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
Symptoms and causes
Probable causes · in order
- Household AC power supply voltage is too high or too lowCommon
Grid voltage sags, brownouts, or surges outside the air conditioner's operating window trigger PC01 protection to safeguard the inverter module and compressor.
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
- Loose terminal connections or damaged wiring at the outdoor unit or reactorPossible
Loose power terminal screws, corroded splices, or disconnected leads on the outdoor reactor or control box cause a sharp voltage drop when the compressor starts.
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
- Faulty reactor, IPM board, or outdoor main electronic control boardLess common
If supply voltage is normal but DC bus voltage between P and N falls outside 310 V, 340 V, or 380 V DC in standby or 220 V~400 V at startup, the reactor, IPM board, or outdoor PCB is faulty.
Evidence: Midea ductless split unit system installation instructions (9000 to 24000 BTU) · Midea ductless split unit system owner's manual (9000 to 24000 BTU) · Midea guía de diagnóstico de averías domésticas PC 01 (protección frente a sobretensión o tensión insuficiente)
Virtual technician
Does PC01 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Midea ductless split unit system installation instructions (9000 to 24000 BTU)
Midea · 2023 · official_doc
- 2
Midea ductless split unit system owner's manual (9000 to 24000 BTU)
Midea · 2023 · official_doc
- 3
Midea México manual de usuario e instalación minisplit R32 MAS12C2AGV32 (Air Volu y Xtreme Plus)
Midea · 2026 · official_doc
- 4
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