Hi and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, the 3 beeps would be a warning indicator; another function is on hold or currently awaiting completion. If have not been done, please check that doors/covers, document support, printing cartridge are all correctly in place as a preliminary consideration.
If these above checks good, would you then be comfortable working using the maintenance mode of the Brother to detect MACHINE ERROR? These are the diagnostics procedures as prescribed by the repair/Service Manual.
As posted above; "...repair/Service Manual..." not just the User's Manual.
For billings & payments including refunds, please contact Customer Support.
For parts only of the Service Manual such as " maintenance mode of the Brother to detect MACHINE ERROR", then this service would have to be accepted / rated positively.
For the whole Service Manual in electronic form, then a token fee as an additional service.
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