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§145.109 Equipment, materials, and data requirements.
(a) Except as otherwise prescribed by the FAA, a certificated repair station must have the equipment, tools, and materials necessary to perform the maintenance, preventive maintenance, or alterations under its repair station certificate and operations specifications in accordance with part 43. The equipment, tools, and material must be located on the premises and under the repair station's control when the work is being done.
(b) A certificated repair station must ensure all test and inspection equipment and tools used to make airworthiness determinations on articles are calibrated to a standard acceptable to the FAA.
(c) The equipment, tools, and material must be those recommended by the manufacturer of the article or must be at least equivalent to those recommended by the manufacturer and acceptable to the FAA.
(d) A certificated repair station must maintain, in a format acceptable to the FAA, the documents and data required for the performance of maintenance, preventive maintenance, or alterations under its repair station certificate and operations specifications in accordance with part 43. The following documents and data must be current and accessible when the relevant work is being done:
(1) Airworthiness directives,
(2) Instructions for continued airworthiness,
(3) Maintenance manuals,
(4) Overhaul manuals,
(5) Standard practice manuals,
(6) Service bulletins, and
(7) Other applicable data acceptable to or approved by the FAA.
the repair station cannot work on a piece of equipment unless they have the proper manuals from the manufacture. garmin does not allow repairs of their boxes by anybody other than garmin. so the repair station cannot do.