U. S. traffic safety regulators have dragged Mercedes-Benz C-Class cars under scanner to investigate a technical glitch in the luxury vehicles' rear light system.

According to a statement by the National Highway Traffic Safety Administration (NHTSA), the stop, tail & turn signal lights in Mercedes-Benz C-Class vehicles can fail due to a melted electrical connector.  Initial investigation has suggested that overheating of connectors caused melting, smoke or fire.

The expanded investigation now covers 252,867 C-Class vehicles manufactured from 2008 through 2011.

The traffic regulator has upgraded the investigation to an engineering analysis, which is a step that could lead to a recall of the vehicles by the regulator.

The NHTSA and the luxury car maker have so far received more than 400 complaints, including 5 fires and 1 injury incidents.  The manufacturer has also reported more than twenty-three thousand warranty claims which could be tied to the issue.

A spokesperson for Mercedes said the manufacturer was fully cooperating with the traffic regulator in the ongoing investigation.  It may be noted here that Mercedes is a subsidiary of German-based luxury auto giant Daimler AG.