GM012 High

Baxi GM012 Fault Code

The Baxi GM012 fault code means: your boiler has detected an internal communication error where a signal meant to confirm it is safe to operate is not being received, causing it to shut down for your protection.. It appears on 1 Baxi model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Contact release signal X16 (0: No; 1: Yes)
Typical repair cost £150-£250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Baxi models that show the GM012 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Baxi GM012 fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026