Fujitsu 99.1 error code

What it means

Fujitsu's outdoor board shows these dot-decimal codes only after an error is active: the red ERROR LED blinks at high speed, then a brief SW1 press makes the MONITOR LEDs blink out the code. Code 99.1 means the outdoor unit is not seeing the expected duty/feedback from one outdoor fan motor.

Urgency

Likely causes

1. Debris, ice, or a foreign object restricting the fan
2. Loose fan-motor plug, damaged fan lead, or bad feedback signal
3. Fan motor winding, phase, or rotation fault
4. Control board fan-drive fault after the motor checks out

Homeowner fix

Turn the system off and look only through the grille for obvious loose debris, snow, or ice. Clear loose debris outside the cabinet, reset once, and stop if the code returns.

When to call a pro

Call a licensed HVAC technician if the fan blade is damaged, the fan is not visibly blocked, or the code returns. Tell them the exact Fujitsu SW1 code is 99.1 and the Section 14-3 meaning is: Fan motor 2 error.

Repair vs replace

Fan motor repairs are usually repairable. Compare replacement only if the diagnosis also includes a major outdoor board, inverter, or compressor repair.

• Fujitsu AIRSTAGE H-series Compact Cassette 9,000 BTU R-32 208/230V (ACUH09KUAS / AOUH09KUAS1)

  AIRSTAGE H-series

• Fujitsu AIRSTAGE H-series Compact Cassette 12,000 BTU R-32 208/230V (ACUH12KUAS / AOUH12KUBS1)

  AIRSTAGE H-series

• Fujitsu AIRSTAGE H-series Floor-Mounted Console 12,000 BTU R-32 208/230V (AGUH12KUAS / AOUH12KUBS1)

  AIRSTAGE H-series

• Fujitsu AIRSTAGE H-series Mid Static Duct 12,000 BTU R-32 208/230V (ARUH12KUAS / AOUH12KUBS1)

  AIRSTAGE H-series

Parts for this line

The parts catalog for Fujitsu AIRSTAGE H-series lists 6 sourced replacement parts for this product line.

For your technician

Technician note: Section 14-3 lists 99.1 as Fan motor 2 error; check fan rotation, motor feedback/duty, connector, harness, fan drive output, and outdoor PCB. Page context: Fujitsu maps this display to the AIRSTAGE H-series line; source: Fujitsu AOUH18-45KWAS/KWAH R-32 Design & Technical Manual; display convention: match the ninety nine and one marker exactly before comparing neighboring codes.

Which systems show it

• Fujitsu Halcyon/AIRSTAGE R-32 AOUH18KWAS2, AOUH24KWAS3, AOUH36KWAS4, and AOUH45KWAS5 outdoor-unit manuals where Section 14-3 lists the same SW1/MONITOR error-code table.
• Fujitsu AOUH18KWAH2 and AOUH36KWAH4 XLTH sibling design manuals where the extracted Section 14-3 table matches the KWAS manuals.

Related troubleshooting

Use the symptom guide alongside the exact display code if the unit is flashing, cycling, or showing comfort symptoms.

Reset note

Turn the system off and look only through the grille for obvious loose debris, snow, or ice. Clear loose debris outside the cabinet, reset once, and stop if the code returns.

Manual trigger

Fujitsu's outdoor board shows these dot-decimal codes only after an error is active: the red ERROR LED blinks at high speed, then a brief SW1 press makes the MONITOR LEDs blink out the code. Code 99.1 means the outdoor unit is not seeing the expected duty/feedback from one outdoor fan motor.

Related codes

Source

Next step