Section 4104 - Testing and approval of equipment(a) Authority of department.--The department may require new vehicles and equipment to be tested and approved for compliance with the requirements of this part or any vehicle equipment standard adopted pursuant to section 4103(a) (relating to promulgation of vehicle equipment standards).(b) Basis of approval.--Approvals may be based on certification furnished to the department by the American Association of Motor Vehicle Administrators, or if the American Association of Motor Vehicle Administrators certification program does not cover the type of vehicle or equipment, the department shall determine approval on test reports prepared by such testing laboratories as the department may designate.(c) Procedure for approval.--The department shall establish by regulation the procedure to be followed when request for approval of any item of equipment is submitted under this section. The department shall not unreasonably withhold designation of any laboratory which meets the minimum criteria established by the department as an approved laboratory for equipment testing. Where a regulated manufacturer has its own in-house testing facilities which meet the minimum criteria, the department may accept test reports from the manufacturer for the purpose of granting equipment approvals.(d) Markings on approved equipment.--Each item of equipment requiring approval by the department shall bear the trademark, name or code symbol under which it is approved. If practicable, the markings shall be legible after installation. For the purposes of this subsection, code symbol means one assigned and approved by the department in the absence of a name or trademark.(e) Lists of approved equipment.--The department shall maintain lists of all items of equipment which have been approved under authority of this part. Copies of the lists or portions of the lists shall be made available at cost upon request. 1976, June 17, P.L. 162, No. 81, § 1, effective 7/1/1977.