Fault Codes / Bosch / A01 (5265)

Bosch A01 (5265)

High

Compress — Z1 PCB disconnected (CAN bus).

Bosch A01 (5265): Z1 PCB disconnected (CAN bus). This fault noticeably affects operation.

Possible causes

CAN bus connection interrupted.

Check steps

Check CAN bus connections.
Check board & power.

Affected parts

Z1-Platine
CAN-Leitung

Safety note

Low voltage — work carefully.

Source: Bosch resmi servis kılavuzu — Cross-verified: code 5265 = Z1 PCB disconnected, CANbus communication fault between heat pump and indoor unit — matches 'Z1 PCB getrennt (CAN-Bus)'.

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

Look up in Enthalio →

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