VW glow plug guidance
This TSB applies to 2009 VW Jetta models, equipped with the CBEA common rail TDI diesel engine. If glow plug testing becomes necessary, do not jump power or ground directly to the glow plugs. The plugs receive pulse width modulated signals from the ECM.
To test, swap a suspected glow plug with a known good glow plug.
Clear out the fault memory and drive the vehicle to see if the concern returns. If the concern moves with the glow plug, replace the glow plug.
If the concern does not move and comes back to the original cylinder, it is recommended that the engine’s harness be inspected. See ETKA for available connectors, terminal ends, etc., for replacement information.