The United States National Highway Traffic Safety Administration has upgraded its investigation into 252,867 Mercedes-Benz C-class cars, covering model years 2008 to 2011, into an engineering analysis, according to documents filed online. An engineering analysis is a step that may lead to a recall of the vehicles by the NHTSA.
According to the documents, the vehicles’ rear light could fail due to an overheated electrical connector. In some cases, overheated connector led to melting, smoke or fire.
NHTSA and Mercedes have received 402 complaints on the issue, including five incidents alleging fire, and one injury, according to documents from the regulator.
A Mercedes spokesman remarked that the carmaker was cooperating with NHTSA's investigation. NHTSA initially launched a preliminary evaluation of the glitch in July 2013 after it received 21 reports of rear light assembly failure due to the melted electrical connector or housing.
According to Mercedes, the overheating of the ground wire was due to corrosion between the connectors in the ground circuit to the tail light. Analysis of the complaint data signified a higher possibility of failure as the vehicles age, so the probe was upgraded to further study the risks and frequency of the issue, according to the NHTSA documents.