Possible Causes

WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

A driver seat cushion over-temp fault can be caused by:

wiring, terminals or connectors.
restricted cushion TED filter.
crushed or restricted cushion foam pad.
crushed or restricted climate controlled seat manifold.
a faulted cushion TED assembly.
a faulted CCSM.