Remove/Install Relay Of ECO Start/Stop Function Auxiliary Battery - AR54.15-S-2002E

Model 447 

With Code MJ8 (ECO start/stop function) 

Except Code D50 (Full-length partition) 

Except Code D51 (Entire partition with 1 window) 

Except Code S23 (Co-driver's seat double seat) 

Model 448 

Courtesy of MERCEDES-BENZ USA

Fig 1: Relay Of ECO Start/Stop Function Auxiliary Battery Components Location - Model 447 With Code MJ8 Except Code D50, D51, S23

Courtesy of MERCEDES-BENZ USA

	Risk of fire  /risk of explosion due to short circuit and escaping oxyhydrogen gas. Risk of (burn) injury caused by caustic burns to eyes, skin and mucous membranes from battery electrolyte/mist, short circuit and arcing. Risk of poisoning  caused by swallowing battery electrolyte or absorption of lead through the skin or body orifices. Risk of death  due to voltage U >= 30 V AC and U >= 60 V DC.	No fires, sparks, open flames, or smoking. Wear acid-resistant gloves, clothing, and glasses. Pour battery acid only into suitable and appropriately marked containers.	AS54.10-Z-0001-01A
Notice	Notes on carrying out repair work in the vehicle interior		AH68.00-D-0001-01KOS
Notice	Information on preventing damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
Notice	Notes on battery		AH54.10-P-0001-01A
	Remove/install
1	Move head restraint on right front seat all the way down.
2	Switch off ignition, remove transmitter key and store it outside of transmission range (min. 2 m).
3.1	Remove cover (3) from right seat base (2).	MODEL 447.6/7, MODEL 448.7
3.2	Starting at the top, unclip and remove stowage compartment (4) from side of right seat base (2).	Model 447.8, model 448.8 Long wedge	Fig 2
4	Remove bolts_(7).	Screw/bolt, seat console to front reinforcement	*BA91.10-Z-1004-01KOJ
5	Remove rear cover (1) from right seat base (2).
6	Lift up floor covering (5) in area of screws (6) and remove screws (6).	Screw/bolt, seat console to body	*BA91.10-Z-1003-01KOJ
7	Tilt seat base (2) far enough forward with front seat mounted until the support battery (G1/12) is accessible, and support the seat base (2) using a suitable wooden block (8).	Make sure that no electric lines are jammed between the seat base (2) and body. Otherwise, the electric lines will be damaged and the electrical system could be damaged.
8	Remove screw (9) and disconnect ground line (10) together with electric line (11) from negative terminal of support battery (G1/12).	Bolt, ground line to backup battery negative terminal	*BA54.10-Z-1005-01KOF
9	Take out screw (16) and, together with electric line (18), remove from positive terminal of support battery (G1/12).	Bolt, busbar to backup battery positive terminal	*BA54.10-Z-1004-01KOF
10	Remove nut (15) and remove busbar (17).	Nut, busbar to relay for backup battery	*BA54.10-Z-1003-01KOF
11	Remove nut (13) and detach electrical wiring harness (14) from on-board electrical system support battery relay (K120).	Nut, wiring harness to backup battery relay	*BA54.18-Z-1003-02KOA
12	Separate electrical connector (12).
13	Remove nuts (19) and remove on-board electrical system support battery relay (K120) from battery carrier (20).
14	Install in the reverse order.

Fig 2: Identifying Long Wedge (115 589 03 59 00)

Courtesy of MERCEDES-BENZ USA