Modern public transport systems are typically designed by following universal aspirations to predictability and standardisation. In the case of Santiago's public transport, however, this design philosophy has often translated into concrete, practical struggles for users with more vulnerable corporealities. In analysing the case of a controversial turnstile installed in Santiago's buses in 2016, this paper draws on video analysis to examine how passengers respond to, and locally deal with, its exclusionary design. Passengers' interactions with this technology demonstrate how the turnstile is taken up as more than a mere sorting device, to become a matter of concern around mobility (in)justice. A detailed analysis of these interactions - through ethnomethodological analysis of video data - describes how passengers respond to the turnstile's exclusionary design by deploying diverse embodied practices of care towards other users experiencing trouble with it. Such practices of care align with a grounded, embodied sense of mobility (in)justice as opposed to more abstract understandings of distributive justice. The paper concludes by discussing the potential forpublic transport systems to become more just and inclusive environments designed as infrastructures of care, whereby materialities may not only allow, but support, practices of care among users.