Defa is at least one vendor making these for renegades. I am getting one fitted for diesel version. As 2.4l trailhawk is not sold here, heater is not listed site but if you know what other cars use same engine you could try searching for that.I guess that depends on if you are asking about the 2.4L gasoline or the 2.0L diesel engine. I don't know where the engine heater element goes in either of those engines, but I do know that a heater element can be installed on the 2.0 diesel. I got one installed on mine when I bought the car.
Ant installation instructions are availlable too http://www.defa.com