Operation CHARM: Car repair manuals for everyone.

Acceleration/Deceleration Sensor: Service and Repair


WM 456155 Replacing combination sensor

Tools





Preliminary work

Preliminary work for removing and installing combination sensor

WARNING

Static battery charge

- Battery can explode
- Electrical discharges

-> Do not rub the battery with a dry cloth.

Information

Switch off all loads and remove the ignition key.

- Do not disconnect the battery while the engine is running.

- Disconnect and reconnect battery with extreme caution.

- Do not rub the battery with a dry cloth.

Information

The combination sensor is located under the centre console.

The functions listed below are integrated into the combination sensor:

- Rate-of-turn sensor

- Lateral acceleration sensor

- Axial acceleration sensor

1. Disconnect the battery. -> 2X00IN General information on disconnecting the battery Procedures
2. Remove centre console. -> 681719 Removing and installing centre console - section on "Removing" 681719 Removing and installing centre console
3. Disconnect electric plug connection for airbag triggering unit.

Removing combination sensor

WARNING

Combination sensor not calibrated or calibrated incorrectly

- Unexpected vehicle handling
- Combination sensor does not function
- Malfunction in combination sensor

-> Calibrate the vehicle after installing or replacing the combination sensor using PIWIS Tester II 9818.
-> Only perform calibration when the vehicle is positioned horizontally and the brake is not actuated.





Installation position of combination sensor

1. Release electric plug connection -2- for combination sensor -1- and pull it off -arrow-.





Removing combination sensor

2. Screw off fastening nuts -3- on the combination sensor -1-.

Installing combination sensor

1. Position the new combination sensor and centre it.
2. Tighten fastening nuts -3-.
Observe correct tightening torques. -> 4X00IN Tightening torques for anti-lock brake system (ABS) 4X00IN Tightening torques for anti-lock brake system (ABS)





Installing combination sensor

3. Plug in electric plug connection -2- on the combination sensor -1- ( -arrow- ) until it engages securely -a-.

Subsequent work

Subsequent work for removing and installing combination sensor

Information

Calibrate the vehicle after installing or replacing the combination sensor. -> 453019 Removing and installing hydraulic unit - section on "Removing and installing" Service and Repair

- Calibration must only be performed with the vehicle ]] standing horizontally with the brakes off [[.

1. Calibrate the combination sensor (includes lateral and axial acceleration sensor) with the help of 2nd generation PIWIS Tester 9818.
To do this, go to the menu:
> Control unit overview
> PSM
> Maintenance/repairs
> Sensor cluster calibration (combination sensor)
This completes the calibration.
2. Connect and lock electric plug connection for airbag triggering unit. -> 695319 Removing and installing airbag triggering unit - section on "Installing" 695319 Removing and installing triggering unit for airbag
3. Install centre console. -> 681719 Removing and installing centre console - section on "Installing" 681719 Removing and installing centre console
4. Connect the battery. -> 2X00IN General information on disconnecting the battery Procedures