Fujitsu CHECK RUN status display

What it means

Check run is a setup/service mode used to verify indoor-unit wiring and piping order. Flashing MONITOR LEDs during this mode are progress/result indications, not fault codes by themselves.

Urgency

Likely causes

1. Indoor/outdoor communication wiring or terminal problem
2. Loose low-voltage connector after service or vibration
3. Power interruption during the control handshake
4. Indoor or outdoor control board fault after wiring is verified

Homeowner fix

If a technician started check run, let them finish. If the system seems stuck in check run, turn it off once and call the installing contractor.

When to call a pro

Call the installer if check run results do not match the installed indoor units, or if the display will not return to normal.

Repair vs replace

This is a status display, not a repair-or-replace decision.

• 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 14-1 starts check run by pressing CHECK for 3 seconds or more and displays connected indoor units before the run. 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 letter C, letter H, letter E, letter C, letter K, letter R, letter U, and letter N 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

If a technician started check run, let them finish. If the system seems stuck in check run, turn it off once and call the installing contractor.

Manual trigger

Check run is a setup/service mode used to verify indoor-unit wiring and piping order. Flashing MONITOR LEDs during this mode are progress/result indications, not fault codes by themselves.

Related codes

Source

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