Mercedes-Benz – How to replace the front end assembly with the front reinforcement

W117, W156, W176, W242, W246
CLA-Class, GLA-Class, A-Class, B-Class
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Engine removal.
Preparation: Remove front module.
Space is needed in the engine compartment.
Remove engine hood and support.
Remove attached air intake hose.
The engine hood lock is behind it.
Remove 3 screws, place lock to one side.
Remove upper 5 screws on bumper.
Raise vehicle.
Remove front wheels.
Remove screw from bottom on inside of wheel arch.
Remove 3 clips from trim.
Remove upper left screw.
Detach cover.
Disconnect daytime running lamp connector.
Disconnect Parktronic connector.
Remove 2 screws from upper bracket of bumper.
On the other side: Disconnect daytime running lamp connector.
Remove the upper screws.
Loosen and remove underfloor paneling.
Obtain assistance from a second person.
Remove front skirt.
Remove headlamps incl. spray nozzles on both sides.
Remove upper 2 fixings on radiator.
Detach wiring harness.
Disconnect connectors for horn, …
… crash sensor and DISTRONIC.
Here: The front module is attached to the absorber with these bolts.
Remove the 3 large bolts and the 1 small bolt at a 90° angle.
Remove 1 bolt at the top left of the front end.
On the other side: remove washer fluid …
… reservoir with connectors.
Remove bolts on front module.
The front module is fully detached.
Obtain assistance from a second person.
Take out front module.
Removal is complete.
Install front module:
First attach front module, lights, washer fluid nozzles and bumper.
Fit front module with bolts and wiring harness, …
.. connectors and both brackets to radiator.
Do not tighten the bolts.
Fit headlamps including spray nozzles.
Fit bumper.
Fit engine hood with lock.
Check gap dimensions:
Between fender and A-pillar 3 mm.
Between engine hood and fender 4 mm.
Between engine hood and headlamp 4 mm.
Between engine hood and bumper 4 mm.
Between bumper and headlamp 4 mm.
Between fender and headlamp 4 mm.
If dimension is +/- 1 mm, correct gap dimension.
Remove bumper again.
Tighten bolts on front module.
Tighten to 120 Nm and protect with wax.
Tighten bolt on upper longitudinal member.
Torque 20 Nm.
Protect bolt with wax.
Install air intake hose and washer fluid reservoir.
Attach bumper and mount wheels.
Attach underfloor paneling.
Calibrate DISTRONIC.
Adjust the headlamps.
Erase fault memory.