Don’t Hotwire Glow Plugs
This bulletin applies to the 2013 Volkswagen Tiguan or any VW equipped with a TDI diesel engine. According to VW, DO NOT test the glow plugs by applying battery voltage to see if they glow. They will become damaged or non-functioning in a very short period of time.
The correct checking procedure is provided in Service Net, under the tab in “Additional Information.”