Remove/Install Front Midrange Radar Sensor - AR54.21-P-0707FR

Model 257 

as of model year 2021 

with code 258 (Collision warning system with active brake application FCW-Stop) 

Model 290 

as of model year 2021 

with code 258 (Collision warning system with active brake application FCW-Stop) 

Shown on model 257 except for code M016 (Performance-enhanced engine) 

Courtesy of MERCEDES-BENZ USA

Shown on model 257 with code M016 (Performance-enhanced engine) 

Courtesy of MERCEDES-BENZ USA

Shown on model 290 

Courtesy of MERCEDES-BENZ USA

Topical note	Notes on preventing damage to electronic components due to a magnetic tool		AH54.00-P-0002-01A
Topical note	Information on preventing damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
	Remove/install
1	Remove Mercedes star.		AR88.40-P-4053FR
2	Remove screw (1).	Model 257 as of model year 2021 with code 258 (Collision warning system with active brake application FCW-Stop)
3	Remove Active Brake Assist controller unit (A108) from holder (2).	Model 257 as of model year 2021 with code 258 (Collision warning system with active brake application FCW-Stop) with code M016 (Uprated engine) Model 290 as of model year 2021 with code 258 (Collision warning system with active brake application FCW-Stop) Do not crush or kink or subject electric lines to tension. This will result in damage to the electric lines and can impair their function.
4.1	Remove holder (2) and remove Active Brake Assist controller unit (A108).	Model 257 as of model year 2021 with code 258 (Collision warning system with active brake application FCW-Stop) except code M016 (Uprated engine)
4.2	Release and disconnect electrical connector (3) and remove Active Brake Assist controller unit (A108).	Model 257 as of model year 2021 with code 258 (Collision warning system with active brake application FCW-Stop) with code M016 (Uprated engine) Model 290 as of model year 2021 with code 258 (Collision warning system with active brake application FCW-Stop)
5	Install in the reverse order.
6	Commission Active Brake Assist controller unit (A108).	When replacing Active Brake Assist controller unit (A108).
			AD00.00-P-2000-06FR
7	Calibrate Active Brake Assist controller unit (A108).
			AD00.00-P-2000-06FR