The National Highway Traffic Safety Administration has stepped up its probe into reports of driver-side door fires in some 2006 and 2007 Chevrolet Trailblazer SUVs.
The probe has been escalated from a preliminary investigation of 167 consumer reports and 698 warranty claims related to door fires, to an engineering analysis. A spokesman for GM said the investigation, which began last February and involved 309,000 Chevrolet Trailblazers, will now include 341,786 vehicles.
Although engineering analyses do not always lead to such severe actions, they are typically the last investigative step in the process that leads to a recall. In some cases, however, the NHTSA closes its investigations if sufficient evidence is not found to warrant a recall.
The GM spokesman said there have no reports of accident, injuries or deaths resulting from the issue, and said the automaker is cooperating with safety regulators in the ongoing probe.
In addition to the NHTSA probe, GM is also conducting an internal investigation of other vehicles from the same model years, including the Buick Rainier, GMC Envoy, Oldsmobile Bravada, Isuzu Ascender and Saab 9-7x, which were built on the same GMT 360 mid-sized SUV platform as the Chevrolet Trailblazer.
The NHTSA said, “The vehicle models and production dates of affected vehicles will be evaluated.”
In an April 20 letter to the NHTSA, General Motors conceded that “In exceptionally rare circumstances, heating could continue until the plastic ignites.”
According to the NHTSA, it has received 83 complaints related to the issue and 66 of those alleged that the door module had been burned or melted. The other 17 complaints involved inoperable or erratic power window switches. Some of the complaints alleged that door fires occurred when the vehicles were keyed off and were unattended.
The Trailblazer was first introduced by Chevrolet in 1999 as a trim level of the Blazer SUV. It became a separate nameplate in 2002. Early models received a Marginal overall safety rating from Insurance Institute for Highway Safety (IIHS). From model-years 2005 through 2009, the Institute awarded the Trailblazer an Acceptable rating.
Annual sales of the Trailblazer peaked in 2004, with 244,150 units being sold. The last Trailblazer rolled of the assembly line on December 16, 2008 but Chevrolet unveiled its next-generation Trailblazer concept model at last year’s Dubai Motor Show, and a production version was unveiled at the Bangkok Motor Show in March.