Compressor Motor Control Error (Rotor Position)

What it means

This code appears on Fujitsu General split and ducted units on the wired remote or indoor display; older models show it as a number of indicator lamp blinks instead of a number. It means the inverter board cannot determine the rotor position inside the compressor motor, which it needs to drive the compressor at the right speed, so the compressor fails to start or stops after a moment. The unit retries and then stops. The same number can mean something different on other brands.

Models covered: Fujitsu General (Fujitsu, O General) split and ducted units that show a two-digit error code on the wired remote or indoor display; older models show errors as lamp blink counts instead.

Related codes: 946384

Symptoms4

• The outdoor unit tries repeatedly to start the compressor without success.
• A short hum or shudder from the compressor, then it stops.
• The outdoor fan runs but there is no cooling.
• The code appears after several start attempts.

Possible causes5

• A loose or burnt wire or terminal on one of the three compressor leads.
• A quick restart after a power cut before pressures equalize.
• Low supply voltage at start-up.
• A fault in the drive circuit or power module (IPM) on the inverter board.
• A seized compressor or damaged windings.

How to diagnose5

1. Switch off at the breaker for at least ten minutes, then restart once.
2. Note whether the code followed a power cut or a period of low voltage.
3. After discharging the board, the technician checks the compressor terminals and wires.
4. The technician measures the three compressor windings and checks they are balanced per the manufacturer specification.
5. The technician tests the inverter board output using the service manual to tell a board fault from a compressor fault.

How to fix5

1. Wait a few minutes after a power cut before restarting, and fit a voltage protector if the supply is weak.
2. Repair or replace compressor wires and terminals.
3. Replace the inverter board at an authorized service center if it is faulty.
4. Replace the compressor if it is seized or its windings are damaged, with evacuation and recharge.
5. Run the unit, confirm the compressor starts smoothly and the code does not return.

Repair cost

In Saudi riyals; the highlighted part is the expected range for this fault.

The cost is low for a wire or weak voltage, higher for a new inverter board, and reaches the top of the range when the inverter compressor must be replaced.

Prices are rough estimates including the part and the technician’s fee, and vary with brand, model and part source.
Prices last updated: September 2026

Frequently asked questions