An Air Canada Airbus A320-200, registration C-FMSX performing flight AC-329 from Montreal,QC to Edmonton,AB (Canada), was on final approach to Edmonton's runway 30 when the crew received an Autobrakes fault indication and performed a missed approach. The crew worked the related checklists, declared PAN PAN and performed a safe landing on runway 30 using alternate braking.
The Canadian TSB reported maintenance found an unserviceable brake servo valve and replaced the valve.