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Brake Fluid: Testing and Inspection



Brake fluid, checking

1. Measuring the quality of the brake fluid with 89 96 985 Brake fluid tester.

NOTE: It is important that the measuring opening is below the fluid surface.

WARNING: Never top up with brake fluid before measuring or the measurement will apply to the new brake fluid and give the wrong quality indication.






If the fluid level is too low for measuring to be performed in the reservoir then a pipette and measuring glass must be used.

If the boiling point falls below 190 °C then the brake fluid must be changed

NOTE: The minimum permissible boiling point for DOT 4 fluid is 155 °C. So that the boiling point does not fall below this level before the next service the fluid needs to be changed if the boiling point falls below 190 °C.

2. Check the level using the MIN and MAX mark on the reservoir.
In the event of fluid shortage, investigate the cause. (Not valid for pre-delivery service.)

In the event of fluid shortage, investigate the cause. (Not valid for pre-delivery service.)

Top up the brake fluid if necessary.

NOTE: Never use brake fluid from open receptacles.