Sensing and acting elements to guarantee the locking functions of seat belt retractors can emit noise when the retractor is subjected to externally applied excitations. For these elements to function correctly, stiffness, inertia and friction needs to be in tune, leading to a complex non-behavior of motion, which makes it delicate to test for vibration induced noise. Requirements for a noise test are simplicity, robustness, repeatability, and independence of laboratory and test equipment. This paper reports on the joint development process for an alternative test procedure, involving three test laboratories with different equipment. In vehicle observation on parcel shelf mounted retractors, commercially available test equipment, and recent results from multi-axial component tests , set the frame for this work. Robustness and reliability of test results is being analyzed by means sensitivity studies on several test parameters. This work results in a proposal for a general test procedure  that allows to characterize at best the noise emitted by the inner components of retractors, being independent from vehicle specific information, but providing a maximum of repeatability and reliability. CEA based tools  a more suitable than retractor bench testing to deal with the vehicle specific integration of retractors.