Fujitsu · Heat pump

6A Display PCB micro communication error

Low severity Fujitsu ductless split/multi/VRF (general code list)Fujitsu wall-mounted 7-15 (NA ASU/AOU type)Fujitsu slim duct ARU 7-18 (LL type)

What the control is telling you

The display board is not communicating with the main board. Indoor lamps: OPERATION (green) flashes 6x, TIMER (orange) flashes 10x, ECONOMY (green) flashes fast nonstop; wired remote shows 6A.

Applies to: Fujitsu ductless heat pumps: Fujitsu ductless split/multi/VRF (general code list), Fujitsu wall-mounted 7-15 (NA ASU/AOU type), Fujitsu slim duct ARU 7-18 (LL type)

Likely causes

Display cable loose
Display or main PCB fault

Test and repair steps

Check the display board cable.
Replace display PCB, then main PCB if needed.

Settings for these units

Operating range and service space · Fujitsu multi-zone outdoor 18/24 type

Other codes on the same units

3A Indoor communication circuit (wired remote) error
5U Indoor unit error (general)
9A Expansion valve coil error
9U Outdoor unit error (general)
11 Serial communication error (indoor/outdoor)
12 Wired remote controller communication error
14 Network communication error
15 Check run unfinished / airflow auto-adjust error

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Source: Fujitsu All Fujitsu split - multi - VRF (generic code list) codes.pdf - section error code table (indoor LED flashes); Fujitsu Wall-mounted 7-9-12-15 (North American trilingual, UTY-RNNUM remotes; e.g. ASU9-12-15 RLF1-RLS familie.pdf - section 14 Error codes; Fujitsu Slim duct AR07-09-12-14-18 (ARU-ARYG LL-type equivalent) installation P-N 9381858064.pdf - section 14 Error codes. Summarized in our own words; check the original manual for your model.

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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.