General Motors (GM) is recalling 6,280 of its Chevrolet Caprice police pursuit vehicles, according to documents filed on the US National Highway Traffic Safety Administration (NHTSA) web site. At issue is the potential for certain vehicles, subject to extended idling times and elevated temperatures of typical police applications, may experience loss of electric power steering (EPS) while driving or idling. The cause is "fretting corrosion" on the connector between the EPS module and torque sensor, the documents say. A loss of power steering would leave manual steering capability, but increases required steering efforts and thereby increase risk of a crash. If power steering is lost, a malfunction indicator light displays and a chime sounds.
Significance: GM became aware of the potential for issue in October 2015, through GM's Holden division – these vehicles are produced in Australia and imported to the US – and began an investigation. No accidents or injuries related to the issue have been reported, although the investigation was started after a complaint from a police department in the US. Although a field action addressed the potential issue for 2014 to 2016 model year Caprice personal-use vehicles, which involved applying dielectric grease to the torque sensor harness, it was not sufficient for the more extreme conditions to which police cars are subject. For vehicles still at the plant, GM will apply an epoxy to the back of the connector and at then interference between the connector and steering gear control unit prior to delivery. For vehicles already sold and in service, dealers will replace the steering gear assembly, under the normal warranty and at no charge to the owner.
