Underbody Components, Checking
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2010 Volkswagen Jetta, 2009 Volkswagen Jetta, 2009 Volkswagen GLI, 2008 Volkswagen Jetta, and 2008 Volkswagen GLI. However, it is still accessible from the selected car via links, so may be relevant.
When checking the underbody protection also check wheel wells and sill panels!
Make sure especially that all the lines are secure in their mountings, and all plugs are present and that there is no damage to the underbody.
On sealing caps -arrows-, check for cracks, displacement and corrosion of underbody guard in particular.
NOTE:
Repair any malfunctions. This can help prevent corrosion and rust-through.