Mercedes Benz C-Class (W204) 2007 - 2014 Training Manual: Bodyshell Structure

Passenger cell

The highly stable passenger cell, designed as a safety cage, forms the core of the body safety concept. Contributing, above all, to its high stability under accidental stresses (head-on, side and rear collisions, as well as rollovers) are:

• Increased use of high-strength, modern high-strength, super high-strength, and hot-formed super high-strength sheet steel and sheet metal with stepped wall thicknesses.
• Materials and sheet thicknesses appropriate for the stresses to the components or structure zones that are severely strained during accidents.
• An optimized forming and cross-section design.

Marking of sectional repairs

"Y" markings are included on the C-pillar paneling and on the outer side of the longitudinal member (below the paneling), which mark the recommended separation points. Joining up the "Y" markings produces an outline for the cut and join.

Bonding of the rear fender to the wheel well with soft adhesive is a new feature. An appropriate repair method is described for this in WIS.

In the case of a repair, the roof paneling is riveted on the left and right in the roof duct instead of being spot welded as in series production.

Note

For reasons of crash safety and durability, the use of two-component repair structural adhesive is absolutely essential.

As a general rule, ultra high-strength hot-formed steel must never be MAG-welded.

Legend

1. Y markings (separation points) for the body
2. Bonding of rear fender

Note

Permissible repair methods are described in the Workshop Information System (WIS).

In general, all areas that are bonded as standard must also be bonded during repairs.