This investigation was prompted by Preliminary Evaluation (PE) 11-017, and was based on reports from consumers alleging that both low beam headlights stopped illuminating simultaneously.Some complainants also reported that the combination switch (switch) that controls the headlights and turn signals, and/or its electrical wiring harness connector were damaged by overheating.ODI's PE information request letter asked Honda for certain data on model years (MY) 2002-2006 CR-V, 2003-2008 Pilot, 2003-2008 Element, 2001-2005 Civic, and 2000-2001 S 2000 vehicles.Analysis of complaint and Honda data show that a complete low beam headlight circuit failure occurs in models with 2-bulb headlight systems (i.e., a single bulb on each side for high and low beam).Models with 2-bulb systems include MY 2002-2004 CR-V, 2003-2005 Pilot, 2001-2003 Civic, and 2003-2008 Element.Models with 4-bulb headlight systems (i.e., two bulbs on each side, one for high and one for low beam) have different electrical circuits for the headlights and do not experience the same failure mechanism as the 2-bulb system.MY 2000-2001 S 2000 models with 2-bulb high intensity discharge headlights also have different electrical circuits for the headlights and do not experience the same failure mechanism.Honda introduced the 4-bulb headlight system in CR-V in MY 2005, in Pilot in MY 2006, and in Civic in MY 2004.On March 29, 2012 Honda submitted a defect information report (DIR) to recall 554,428 vehicles, including MY 2002-2004 CR-V and MY 2003 Pilot.In the DIR, Honda stated that tension from the combination switch wiring harness to the electrical terminal for the low beam headlight circuit could cause a small amount of motion as the combination switch was operated.This motion, over time, can wear the surface of the terminal creating copper oxide, increasing electrical resistance, which may cause the terminal to melt within the harness connector.ODI continued its investigation, and on August 31, 2012 Honda submi