6512Brake Fluid Tester for DOT4


This tester can be used as a digital brake fluid tester suitable for determining brake fluid quality. Develop for professional use in automotive repair shops.


  • Suitable for DOT4.
  • Battery: 1.5V AAA
  • Brake fluid characteristics varied with different brands.
  • Auto Power-Off function.
  • With CE and UKCA Approval.


  1. Press switch to turn on green LED illumination to indicate battery OK (red LED means replace battery).
  2. Tester has auto-off function.
  3. Immerse probe of the tester into brake fluid (probe tip must be at least 10mm above bottom of fluid reservoir).
  • LED green: brake fluid H2O < 1.5%, brake fluid/battery OK.
  • LED yellow: brake fluid H2O: 1.5% to 3%, low percentage of water, check again within 6 months.
  • LED red: brake fluid H2O > 3%, change brake fluid/change battery.
Calibration Check:
  • To confirm correct operation, immerse probe in plain water and red LED will illuminate if tester is operating correctly.
  • Remember to dry tester before using in brake fluid.
Battery Installation:
  1. Remove switch cap.
  2. Withdraw circuit board.
  3. Fit battery-positive towards LED.
  4. Slide circuit board into case, ensuring it engages in slots on side of case.
  5. Lay back switch cap.