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Home >> Mercedes Benz >> 2021 >> A220 Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Accessories Control Systems >> Electrical System, Equipment & Instruments - 177 Chassis (2 Of 4) >> Testing & Repair >> Remove/Install Active Brake Assist Electric Controller Unit >> Remove/Install Active Brake Assist Electric Controller Unit - AR54.21-P-0700MFA
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Remove/Install Active Brake Assist Electric Controller Unit - AR54.21-P-0700MFA

Model 118, 177, 247 

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

except code 772 (AMG styling - Front spoiler, side skirts) 

Fig 1: Active Brake Assist Electric Controller Unit Components Location - Model 177 With Code 258 Except Code 772
G15492015REMOVINGINSTALLINGREFER TO SELF-DIAGNOSTIC SYSTEMSREFER TO SELF-DIAGNOSTIC SYSTEMSCourtesy of MERCEDES-BENZ USA
Notice  Notes on preventing damage to electronic components due to a magnetic tool   AH54.00-P-0002-01A
Notice  Information on preventing damage to electronic components due to electrostatic discharge   AH54.00-P-0001-01A
REMOVINGINSTALLING Remove/install     
1.1 Remove front section of front fender liner. Model 118, 177, 247
with code 258 (Collision warning system with active brake application FCW-Stop)
except code 228 (Additional warm water heating)
except code 772 (AMG styling - Front spoiler, side skirts)
 
      AR88.10-P-1301MFA
1.2 Remove front bumper and place down on suitable mat. Model 118, 177, 247
with code 228 (Additional warm water heating)
with code 258 (Collision warning system with active brake application FCW-Stop) except code 772 (AMG styling - Front spoiler, side skirts)
 
      AR88.20-P-2000MFA
2 Release and disconnect electrical connector from Active Brake Assist controller unit (A108)    
3 Unhook Active Brake Assist controller unit (A108) from retaining tab and remove from bracket (1).    
4 Install in the reverse order.    
5.1 Commission Active Brake Assist controller unit (A108). If the Active Brake Assist controller unit (A108) has been replaced.  
REFER TO SELF-DIAGNOSTIC SYSTEMS     AD00.00-P-2000-06MFA
5.2 Perform calibration of Active Brake Assist controller unit (A108). If Active Brake Assist controller unit (A108) is reused.  
REFER TO SELF-DIAGNOSTIC SYSTEMS     AD00.00-P-2000-06MFA