Dead-ended anode operation has a number of practical advantages that simplify system complexity and lower cost for polymer electrolyte fuel cells. However, dead-ended mode leads to performance loss over time which can only be reversed by performing intermittent purge events. This work applies a combined hydro-electro-thermal analysis to an air-cooled open-cathode fuel cell, presenting experimental functional maps of water distribution, current density and temperature. This approach has allowed the identification of a 'nitrogen blanketing' effect due to nitrogen cross-over from the cathode and a 'bypass' effect where a peripheral gap between the gasket and the GDL offers a hydrogen flow 'short circuit' to the border of the electrode. A consequence of high local current density at the margin of the electrode, and resulting high temperatures, may impact the lifetime of the cell in dead-end mode. (C) 2016 Elsevier Ltd. All rights reserved.