Disconnect the bleeder unit for the brake fluid

NOTE: RISK OF DAMAGE
Paint damage.
Mechanical or chemical action may lead to paint damage.

Switch off bleeder unit (1) and remove it from the brake fluid expansion tank.
Check the brake fluid level and adjust it to the maximum mark if necessary.

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Check the seal (1) of the sealing cap for damage, replace if necessary.
Mount the sealing cap on the brake fluid expansion tank.

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Follow-up work

If installed: check the GAS PRESSURE SPRING for bonnet (only for versions with active pedestrian protection (SA8TF))
Perform the CBS RESET