Control Unit, Def Heater: Description: Description
WARNING: This page is about a different car, the 2016 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Heater Control Unit
Courtesy of CHRYSLER GROUP, LLC
The Diesel Exhaust Fluid (DEF) Heater Control Unit (HCU) (2) is located in the left rear wheel well liner.