Brake Fluid Tester – shoprexo
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    Brake Fluid Tester

    $19.97 $39.97
    Unit price  per 

    Staying safe and knowing that your car is in top condition is most important. Ideally, brake fluid should be checked regularly and changed every one to two years. As moisture seeps into the brake system through the brake hoses and seals the brake fluid will become contaminated and the danger of brake failure will increase.

    This pen-shaped brake fluid tester can easily help determine whether it's time for you to change your brake fluid. Brake Fluid Tester is to determine the moisture change brake fluid based on the change in conductivity. It shows clearly the extent of moisture contained by the light-emitting diode, high moisture content in brake fluid will lead to lower boiling point, hence affect the braking performance.

    Red indicates the brake fluid needs immediate replacement, green represents good condition, yellow indicates the state is acceptable but soon replaced. 


    1. Turn on the brake fluid tester by pressing the button. A green light should light up. If the light does not come on, it may be time to replace the battery.
    2. Unscrew the lid for the brake fluid reservoir, and take off the cap for the brake fluid tester.
    3. Dip the test probes into the brake fluid and the LED lights will indicate the percentage of water in the brake fluid.
    4. After testing, screw the lid of the brake fluid reservoir back on tightly.
    5. The tester will automatically power off after 12 seconds of inactivity.

    The LED lights will indicate the percentage of water in the brake fluid:
    Green: None
    Green/Yellow: Less than 1%
    Green /Yellow/Yellow: Approx. 2%
    Green/Yellow/Yellow/Red: Approx. 3% (Time to change brake fluid.)
    Green/Yellow/Yellow/Red/Red: Approx. 4% (Change brake fluid immediately!)


    • This brake fluid tester is calibrated for DOT 4 brake fluid only, which is used in most cars produced since 2006.
    • Replace the battery if the green LED light no longer lights up after you press the button.
    • Rinse the test probe with tap water after every use.
    • In case of skin contact with brake fluid, thoroughly wash the affected skin or clothing with water.
    • Do not expose brake fluid to the atmosphere for a long time as it is highly hygroscopic.
    • Operate using 1 X AAA battery (not included).