WARNING: This page is about a different car, the 2009 Honda S2000, 2008 Honda S2000, 2007 Honda S2000, and 2006 Honda S2000. However, it is still accessible from the selected car via links, so may be relevant.
As the accelerator pedal position changes, the sensor varies the signal voltage to the ECM.
Fig 1: Identifying Accelerator Pedal Position Sensor