Volkswagen Group of America’s Audi unit has announced a recall of certain 2013-2016 Audi A4, A5 and Q5 vehicles. The National Highway Traffic Safety Administration (NHTSA) said the electrical connector of the auxiliary heater is susceptible to contact corrosion, which may cause the auxiliary heater to fail and/or cause the wires to overheat and melt. Further, melting wires usually leads to an open circuit, but it can also lead to overheating which could result in a fire.
According to reports, the company cost-reduced the connectors a few years ago by changing the connector make-up from tin and silver to just tin. It turned out that the tin-only version was more susceptible to environmental attack. In 2015 they reversed course and went back to the silver-tin combination.
Mechanical strain on the electrical connector and micro movements may lead to contact corrosion and fretting, said the NHTSA report. Tin-only coated connectors are less resistant to this phenomenon. As a consequence, increased transition resistance may occur and could raise temperatures.
The recall affects more than 200,000 vehicles. Volkswagen’s numbers for this recall are 80C5 and 80C6.