The National Highway Traffic Safety Administration is currently investigating the 2005 and 2006 Mercedes-Benz E-Class for a wiring harness issue that could prevent the airbags from deploying in a collision. There are about 100,000 vehicles that could be affected if a recall notice is issued, and NHTSA says that it's received four complains of failures of the wiring harness, though there have been no reported injuries as a result of the issue.
Mercedes spokesman Robert Moran reportedly told Bloomberg that the condition presents itself when drivers telescope the steering wheel all the way out and and as high as it can go. Under those conditions the potentially defective harness could pull out of the connector block, causing an open-circuit condition in the driver's airbag circuits. If the harness disconnects from the connector, the air bag warning lamp will illuminate and one of two diagnostic fault codes will point to the problem. The German automaker sent out a TSB back in December 2005 to address the issue, which is fixed with what NHTSA calls a "substantially longer" wiring harness. The TSBs, which have been updated over time, covers MY 2003-2009 E-Class and the MY 2006-2010 CLS, though only the 2005 and 2006 E-Class is currently being investigated. Hit the jump to read over the NHTSA summery of the investigation.
ODI has received four complaints of steering column module wiring harness failures on MY 2005-2006 Mercedes-Benz E-Class vehicles. In December 2005, Mercedes-Benz USA issued a technical service bulletin (TSB No. P-B-91.60/99) and subsequently issued several minor revisions to the original TSB. The TSBs address reports of air bag warning lamp illumination accompanied by a diagnostic fault code 9103 or 9123 indicating a high resistance in the driver's frontal air bag ignition squib 1 or 2 (the air bag firing circuits), respectively. This condition may result in failure of the driver's first stage and/or second stage inflator to deploy in the event of an above deployment threshold frontal crash. According to the TSBs, the repair involves significant lengthening of the steering column module wiring harness by cutting and splicing each wire in the harness. Thus, it appears possible that the wire ends in the original, shorter harness could pull out of the connector block thereby causing an open-circuit condition in the driver's air bag circuits. Additionally, the TSBs cover MY 2003-2009 E-Class and MY 2006-2010 CLS-Class vehicles. Although ODI has not received complaints involving all of these vehicles, ODI will inquire about all vehicles covered by the above TSBs.