Rain/Light Recognition Sensor -G397-, Removing and Installing
Special tools and workshop equipment required
Removing
- Turn off the ignition.
- Vehicles with ignition lock: Remove the key.
- Remove the interior rearview mirror. Refer to → Body Interior; Rep. Gr.68; Interior Rearview Mirror; Interior Rearview Mirror, Removing and Installing.
- Disconnect the connector -3-.
- Insert a narrow screwdriver -5- into the opening as shown and release the retaining tabs -2- in direction of -arrows-.
- Wait one minute so that the silicon pad can release without leaving any residue.
- Loosen the Rain/Light Recognition Sensor -G397--4- by moving it back and forth and remove it from the mount -1-.

Caution
Risk of damage to the humidity sensor.
Installing
Install in the reverse order of removal. Note the following:
Note
Replace the silicon pad and retainer.
- Release the retaining tabs on the retainer -1--arrows- and remove it from the sensor -2-.

- Press on the new retainer until it audibly engages.
- Clean the adhesive surface on the windshield with Cleaning Solution -D 009 401 04-.

- Remove the silicone pad -2- cleanly from the sensor -3-.
- Clean the adhesive surface -1- on the sensor with Cleaning Solution -D 009 401 04-.

- Remove the silicone paper -1- from the silicone pad -3-.
- The clear protective film -2- remains on the silicone pad as an assembly aid.

- Center the silicone pad -2- on the sensor -3- using the clear protective film -1-.
- Press the silicone pad through the protective film onto the sensor without forming any bubbles.
Note
To avoid contaminating the silicone pad, remove the protective film just before installing it.

- Remove the protective film -2- from the silicone pad -1-.
- Spray the entire surface of the silicone pad with the Cleaning Solution -D 009 401 04-.
- Insert the sensor -4- into the mount -2-.
Caution
The Rain/Light Recognition Sensor -G397- must have no embedded objects or bubbles between it and the windshield to function correctly.
- Press the retaining clips -1 and 5- until they audibly engage.

- Connect the connector -3-.

Rain/Light Recognition Sensor -G397-, Replacing
Special tools and workshop equipment required
Removing
- If replacing the control module, select the "Replace Control Module" function Vehicle Diagnostic Tester.
- Turn off the ignition.
- Vehicles with ignition lock: Remove the key.
- Remove the interior rearview mirror. Refer to → Body Interior; Rep. Gr.68; Interior Rearview Mirror; Interior Rearview Mirror, Removing and Installing.
- Disconnect the connector -3-.
- Insert a narrow screwdriver -5- into the opening as shown and release the retaining tabs -2- in direction of -arrows-.
- Wait one minute so that the silicon pad can release without leaving any residue.
- Loosen the Rain/Light Recognition Sensor -G397--4- by moving it back and forth and remove it from the mount -1-.
- Clean the adhesive surface on the windshield with Cleaning Solution -D 009 401 04-.

Installing
Install in the reverse order of removal. Note the following:
Caution
Risk of damage to the humidity sensor.

- Press the grip surfaces -arrows- on the protective cap -2- gently together and remove from the sensor -1-.
Note
To avoid contaminating the silicone pad, remove the protective cap just before installing it.
- Spray the entire surface of the silicone pad -3- with the Cleaning Solution -D 009 401 04-.
- Insert the sensor -4- into the mount -2-.
Caution
The Rain/Light Recognition Sensor -G397- must have no embedded objects or bubbles between it and the windshield to function correctly.
- Press the retaining clips -1 and 5- until they audibly engage.
- Connect the connector -3-.

- After replacing the rain/light recognition sensor, it must be re-coded in "Guided Functions". Refer to Vehicle Diagnostic Tester.

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