Cartisan recently received a service request from a BMW 320d E90. The iDrive system of the E90 displayed a warning that the brake fluid needed to be replaced.
A quote was provided and once the customer agreed, the car was brought to the workshop
As soon as the car reached the workshop it was parked in the service bay and raised up with the help of a lift.
The bonnet was popped open and the service began. The cap of the brake fluid reservoir was opened so as to prevent any sort of air blocks within the brake lines.
The 4 wheels were removed and all 4 of the brake calipers were disconnected from the brake rotors.
The brake pads were removed from the calipers and cleaned using a sandpaper to rid the surface of the pad of brake dust and dirt.
It was also confirmed that all 4 brake pads were in good condition
Once the brake pads were cleaned, they were placed back into the brake calipers which were mounted and bolted back onto the brake rotors. The assembly was also blown with pressurized air to rid it of any brake dust and stubborn dirt.
The technician then disconnected the brake fluid line from the brake cylinder while another technician pumped the brake pedal. This resulted in brake fluid flowing out of the fluid lines along with any air bubbles if present. Once all the bubbles were out of the lines, the brake fluid lines were refitted to the cylinder immediately to avoid further formation of air bubbles.
This process is called brake bleeding was repeated for the 3 other wheel cylinders.
Once the brake bleeding was completed, the brake fluid reservoir was topped up with DOT4 brake fluid from Bosch.
The car was then taken for a test drive to confirm that the braking system was working well and the brake fluid replacement was a success.
The service warning on the iDrive system was then reset and the car was delivered back to the customer.