Fujitsu 5U.1

Medium

Airstage V-II — Signal amplifier auto address setting error (Error code 5U.1).

Fujitsu 5U.1: Signal amplifier auto address setting error (Error code 5U.1). This fault usually isn't an immediate stop, but should be checked soon.

Possible causes

Power supply defective.
Outdoor unit address/number-of-units setting mistake.
Communication line between outdoor units defective.

Check steps

Check power supply (cable, on/off).
Check address/number-of-units setting.
Check communication wiring; replace main PCB if unresolved.

Affected parts

Kommunikationskabel
Hauptplatine

Safety note

Isolate power before testing.

Source: Fujitsu Airstage V-II VRF Service Manual, "Error Code List For Outdoor Unit" p.65 + "Trouble Shooting With Error Code (Outdoor Unit)" p.82ff (ManualsLib scan of official manual)

Reviewed by Anıl Güzeldemir — in the refrigeration machine room since 2006, developer of Enthalio.

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Related fault codes

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