Remove/install front seat backrest frame - AR91.10-P-3331MCU

MODEL 451.3/4 

Shown on left front seat 

Fig 1: Identifying Front Seat Backrest Frame Remove/Install Components - Shown On Left Front Seat

Courtesy of MERCEDES-BENZ USA

Shown on right front seat 

Fig 2: Identifying Front Seat Backrest Frame Remove/Install Components - Shown On Right Front Seat (1 Of 2)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Front Seat Backrest Frame Remove/Install Components - Shown On Right Front Seat (2 Of 2)

Courtesy of MERCEDES-BENZ USA

	Removing
	Risk of injury  caused by backrest suddenly folding forward if release lever is accidentally operated during inspection and repair work	When working on the seat, be careful not to accidentally release the backrest mechanism allowing the seat to fold forward. Keep body parts clear of the backrest travel area.	AS91.00-Z-0005-01V
	Risk of injury  caused by performing testing or repair work on airbag or emergency tensioning retractor units.	Store airbag units with deployment side facing up; do not expose to temperatures greater than 100 °C. When working on these units, disconnect the power supply.	AS91.00-Z-0001-01A
	Notes on avoiding damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
1.1	Remove driver seat	When removing backrest frame (2) from driver seat.	AR91.10-P-1010MCU
1.2	Remove passenger seat	When removing backrest frame (2) from front passenger seat.	AR91.10-P-1020MCU
2	Remove bolt (5), place seat belt buckle (1) with wiring harness for seat belt buckle (4) to one side and detach grommet (6) from backrest frame (2)
3	Remove foam part for backrest		AR91.10-P-1120MCU
4	Fold backrest frame (2) forward
5	Unclip belt tension sensor connector (B48/3x1) from the retaining plate (10)	When removing backrest frame (2) from front passenger seat.
6	Unclip clip (11)	Only if the clip (11) has been installed and when the backrest frame (2) is being removed from the front passenger seat.
7	Remove retaining plate (10)
8	Remove bolts (3) of backrest frame (2)
9	Remove backrest frame (2)
10	Remove fuse (9)	When replacing the backrest frame (2).
11	Remove armrest support	For vehicles with code (I50) Armrest or with retrofitted armrest
	Install
12	Install support for armrest	For vehicles with code (I50) Armrest or with retrofitted armrest
13	Clip retainer (9) to backrest frame (2)	When replacing the backrest frame (2).
14	Position backrest frame (2) on seat console and screw in bolts (3) up to contact surface
15	Screw in bolts (3) opposite the seat belt buckle (1), starting from the front. Move backrest frame (2) to its rearmost position and lock in place. Screw in bolts (3) in vicinity of seat belt buckle (1), starting from the rear. While doing so, press the backrest frame (2) backwards.		*BA91.10-P-1002-01P
16	Fit retaining plate (10) to backrest frame (2)
17	Attach the clip (11)	Only if the clip (11) has been installed and when the backrest frame (2) is being removed from the front passenger seat.
18	Clip the belt tension sensor connector (B48/3x1) to the retaining plate (10)	When installing front passenger seat backrest frame (2).
19	Install foam part for backrest	Before installing the foam part for the backrest, check the installation position (arrows) of the spring frame (7), and correct if necessary.	AR91.10-P-1120MCU
20	Insert grommet (6) into backrest frame (2), position seat belt buckle (1) with wiring harness for seat belt buckle (4) on backrest frame (2) and screw in bolt (5).		*BA91.40-P-1003-01G
21.1	Install driver seat	When installing driver seat backrest frame (2).	AR91.10-P-1010MCU
21.2	Install front passenger seat	When installing front passenger seat backrest frame (2).	AR91.10-P-1020MCU