Crash Element (Before And After Compression):

Fig 1: Identifying Crash Element (Before)

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Fig 2: Identifying Crash Element (After)

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NOTE: Never disassemble the steering column to perform repairs on the crash element! In the event of a defect (particularly a crash), replace the entire steering column.

Always set the steering wheel in the straight ahead position before removal/installation. Remove/install the steering column switch center (SZL) in the straight ahead position, also observe the marking on the locking tooth when installing the steering wheel.

Steering Angle Sensor: The steering angle sensor is integrated in the Steering Column Switch Center (SZL) module. The steering angle positions are transferred by Bus signals to other control modules.

Fig 3: Identifying Steering Angle Sensor

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The steering angle sensor is a 3.4 kOhm potentiometer with two wipers offset by 90 degrees. From the two wiper signals and a reference signal, the SZL calculates the steering angle sensor position and transfers it over the Byteflight and CAN Bus to other control modules. Shorts to B+ or ground are detected as faults.

Fig 4: Identifying Steering Angle Sensor Communication Link

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NOTE: When replacing the SZL with the integrated steering angle sensor, the coil spring cassette must be installed in the center position with the wheels set in the straight ahead position. The wiper does not have an electrical reference point and steering angle matching must be performed with the DISplus after repairs.

After performing the steering angle matching, self-learning with the front wheel speed signals is necessary to determine the number of steering wheel turns. The number of steering wheel turns is necessary for determining the exact steering angle.

Chassis Integration Module (CIM): The CIM is located on the underside of the steering column.

The CIM controls the following functions:

Servotronic
Electric steering column adjustment

Fig 5: Identifying CIM Location
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The CIM is linked to the K-CAN S Bus for communication with other control modules. The ZGM provides the gateway for diagnostic communication.

Fig 6: Identifying CIM Communication Link

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