Abstract: An inline fan reverser (100) and related method for clearing away debris from a radiator (20) by programmatically reversing a vehicle's radiator fan (30). The fan reverser (100) electrically connects, inline, with the conductors that normally drive the electric motor (32) that turns the fan (31) in order to pull cooling air through the radiator (20) The fan reverser (100) includes a microcontroller that initially clears the radiator (20) of debris by pushing or blowing for a short period of time (e.g. 10 seconds) and then enters a main loop where the fan reverser repeatedly transitions between a cooling phase and a cleaning phase. In the cooling phase, the reverser pulls air through the radiator for a long period of time (e.g. 10 minutes). In the cleaning phase, the reverser periodically clears the radiator (20) of debris by pushing or blowing for a short period of time (e.g. 10 seconds). The reverser also provides for short OFF periods (e.g.