Replacing Backrest Frame
Replacing Backrest Frame
Technical values
Preliminary work
1. Remove cushion carrier. Refer to Removing and installing cushion carrier for front backrest.
INFORMATION: Only for vehicles with lumbar support.
2. Remove control valve for lumbar support adjustment. Refer to Removing and installing control valve for lumbar support adjustment.
INFORMATION: Only for vehicles with lumbar support.
3. Remove lumbar support. Refer to Removing and installing lumbar support.
INFORMATION: Only for vehicles with lumbar support.
4. Remove motor for lumbar support. Refer to Motor for lumbar support.
INFORMATION: Only for vehicles with adaptive sports seats.
5. Remove air cushion for backrest. Refer to Removing and installing air cushion for backrest.
Disassembling backrest frame
Removing foam part
1. Remove foam part -1- at the headrest.
Removing supports for backrest side parts
1. Unscrew fastening screws -1- and remove support for right backrest side part -2-.
2. Unscrew fastening screws -1- and remove support for left backrest side part -2-.
Removing inner spring on backrest frame
1. Disengage tension springs -1- at left and right on inner spring -2- (-arrows A-).
2. Unclip inner spring -2- on backrest frame at the drive shaft -arrow B- and remove inner spring.
3. Disengage tension springs -1- on the backrest frame.
Disconnecting wire harnesses on backrest frame
INFORMATION:
- Only for vehicles with lumbar support.
- Make sure not to trap or damage the wire harness when pulling it through.
1. Pull wire harness for backrest -1- down out of the backrest frame -2-.
2. Turn plug connection -1- approx. 90° anti-clockwise -arrow A- and pull it off the backrest frame -arrow B-
3. Release plug connection -arrows C- and disconnect it -arrows D-.
INFORMATION: Make sure not to trap or damage the wire harness when pulling it through.
4. Press locking tabs on fixing clip -2- together and unclip it -arrow E-. Pull wire harness for backrest -3- down and out -arrow F-.
5. Press locking tabs on fixing clip -2- together and unclip wire harness for side airbag -4- from the backrest frame -arrow G-.
Removing frame for side airbag
1. Unscrew fastening screws -1- and unclip frame for side airbag -2- from the backrest frame -3-.
Disassembling backrest frame
1. Remove fastening nuts -1- from the backrest frame -2-, check them and replace if necessary.
2. Unclip fixing clips -1- from the backrest frame -2-, check them and replace if necessary.
Removing backrest frame
INFORMATION: Two persons are needed to remove and install the backrest frame.
1. Secure backrest frame -2- in upright position.
2. Unscrew fastening screws -1- on left and right and remove backrest frame -2- up out of the seat frame.
Assembling backrest frame
Installing backrest frame
DANGER: Loosen the safety screws.
- Danger of injury if front seat is not screwed down correctly.
- Always replace fastening screws for the front seat after customer service and reworking.
- It is not permissible to make alterations to the micro-encapsulated screws (e.g., use lubricant, loosen bolts, and screw them down again).
INFORMATION: Two persons are needed to remove and install the backrest frame.
1. Fit backrest frame -2- into the seat frame, position it correctly and secure with the fastening screws -1-. Tightening torque: 34 Nm (25 ftlb.)±4 Nm (±3 ftlb.)
Assembling backrest frame
1. Press in fixing clips -1- on the backrest frame -2-.
2. Screw fastening nuts -1- onto the backrest frame -2-.
Installing frame for side airbag
1. Clip frame for side airbag -2- to backrest frame -3- and secure with the fastening screws -1-.
Securing wire harnesses on backrest frame
INFORMATION:
- Only for vehicles with lumbar support.
- Make sure not to trap or damage the wire harness when pulling it through.
1. Pull wire harness for backrest -1- up into the backrest frame -2-.
2. Press fixing clip -2- on wire harness for side airbag onto the backrest frame -arrow A-.
INFORMATION: Make sure not to trap or damage the wire harness when pulling it through.
3. Pull wire harness for backrest -3- through -arrow B- and press in fixing clip -2- (-arrow C-).
4. Push plug connection -1- together -arrows D- until it engages securely.
5. Insert plug connection -1- into the backrest frame -arrow E- and turn it clockwise by approx. 90° -arrow F-.
Installing inner spring on backrest frame
1. Engage tension springs -1- in the backrest frame.
2. Clip in inner spring -2- on lower part of backrest frame at the drive shaft -arrow A-.
3. Engage tension springs -1- in the inner spring -2- on the backrest frame -arrow B-.
Installing supports for backrest side parts
INFORMATION:
- Observe hose routing.
- In vehicles with lumbar support, make sure the hoses are routed correctly in the area of the backrest side support.
1. Insert support for left backrest side part -2- and secure with the fastening screws -1-.
2. Route wire harness for side airbag -1- as shown behind the backrest side part support -2-.
INFORMATION:
- Observe hose routing.
- In vehicles with lumbar support, make sure the hoses are routed correctly in the area of the backrest side support.
3. Insert support for right backrest side part -2- and secure with the fastening screws -1-.
Fitting foam part
1. Fit foam part -1- to the headrest.
Subsequent work
INFORMATION: Only for vehicles with adaptive sports seats.
1. Install air cushion for backrest. Refer to Removing and installing air cushion for backrest.
INFORMATION: Only for vehicles with lumbar support.
2. Install motor for lumbar support. Refer to Motor for lumbar support.
INFORMATION: Only for vehicles with lumbar support.
3. Install lumbar support. Refer to Removing and installing lumbar support.
INFORMATION: Only for vehicles with lumbar support.
4. Install control valve for lumbar support adjustment. Removing and installing control valve for lumbar support adjustment.
5. Install cushion carrier. Removing and installing cushion carrier for front backrest.