LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mercedes Benz >> 2018 >> S450 Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Collision/Avoidance >> Electrical System, Equipment & Instruments - 222 Chassis (05 Of 10) >> Testing & Repair >> Remove/Install DC/DC Converter Control Unit For Windshield Heater >> Remove/Install DC/DC Converter Control Unit For Windshield Heater - AR54.21-P-1603LF
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Remove/Install DC/DC Converter Control Unit For Windshield Heater - AR54.21-P-1603LF

Model 222 

With Code 597 (Heated windshield) 

except code B01 (48V technology) 

Fig 1: Windshield Heater Control Unit Components Location - Model 222 With Code 597 Except Code B01
G15370507WARNINGREMOVINGINSTALLINGIMPORTANTINSTALLATION IMPORTANTTORQUE SPECIFICATIONTORQUE SPECIFICATIONCourtesy of MERCEDES-BENZ USA
WARNING Risk of injury.  Moving parts can pinch, crush or, in extreme cases even sever extremities. No parts of the body or limbs should be within the operating area of mechanical components when moving components. AS00.00-Z-0009-01A
Topical note  Information on preventing damage to electronic components due to electrostatic discharge   AH54.00-P-0001-01A
  Notes on HANDS-FREE ACCESS   AH80.61-P-0001-01A
REMOVINGINSTALLING Remove/install     
1 Detach ground line of on-board electrical system battery   AR54.10-P-0003LF 
2 Remove luggage compartment lining on right Model 222
with code 597 (Heated windshield) except code B01 (48V technology)
 
      AR68.30-P-4600LF
3 Disconnect electrical connection on AdBlue® control unit Model 222
with code 597 (Heated windshield) with code U77 (Diesel Emission control BLUETEC (SCR)) except code B01 (48V technology)
IMPORTANT The AdBlue® control unit is mounted on the control unit bracket (2).
 
4 Remove electrical wiring harness (1) from control unit holder (2) INSTALLATION IMPORTANT Replace damaged fasteners.  
5 Open cover (3)    
6 Remove positive line (4) from windshield heater control unit (N61) TORQUE SPECIFICATION Nut, line to windshield heater control unit *BA54.21-P-1001-01D 
7 Remove ground line (5) from windshield heater control unit (N61) TORQUE SPECIFICATION Nut, line to windshield heater control unit *BA54.21-P-1001-01D 
8 Disconnect electrical connector (6)    
9 Remove bolts (7)    
10 Unscrew nut (8)    
11 Take control unit holder (2) with windshield heater control unit (N61) out of trunk    
12 Unscrew screws (9) and remove windshield heater control unit (N61) from control unit holder (2) When replacing windshield heater control unit (N61).  
13 Install in the reverse order    
CONTROL UNITS

Number Designation Model 222
BA54.21-P-1001-01D Nut, line to windshield heater control unit Nm 9