Brake Fluid Tester – Boiling Point Measurement Method

This brake fluid tester is designed for measuring the boiling point of brake fluid to evaluate its condition and determine whether replacement is necessary. The boiling point temperature serves as an important maintenance reference, helping technicians assess the moisture content within the brake fluid.

As brake fluid absorbs moisture over time, the boiling point decreases, potentially reducing braking performance and increasing the risk of brake fade under high operating temperatures. By accurately measuring the boiling point, technicians can determine when brake fluid service is required.

The tester can also be used as a temperature measuring device for other liquids when connected to a compatible K-type thermocouple sensor.

Suitable for passenger cars, motorcycles, and light commercial vehicles using DOT 3, DOT 4, DOT 4 PLUS, or DOT 5.1 brake fluids.

Technical Specifications

Brake Fluid Compatibility

• DOT 3
• DOT 4
• DOT 4 PLUS
• DOT 5.1

Power Supply

• 12 V vehicle battery

Test Current

• 5 – 7 A

Operating Temperature

• 0 °C to 50 °C

Boiling Point Measurement

• Measurement accuracy: ±5%

Temperature Measurement

• Measuring range:
  • -60 °C to 500 °C
  • (-76 °F to 932 °F)
• Measuring accuracy:
  • -20 °C to 500 °C
  • ±(1% + 3 digits)

Applications

• Brake fluid condition testing
• Brake fluid boiling point measurement
• Brake system maintenance
• Moisture content evaluation in brake fluid
• Temperature measurement of liquids using K-type sensor
• Workshop and vehicle maintenance applications

Technical Features

• Accurate boiling point testing method
• Helps determine brake fluid replacement intervals
• Supports multiple DOT brake fluid specifications
• Additional temperature measurement function
• Powered directly by vehicle battery
• Durable workshop-grade construction
• Suitable for professional service applications

Brake Fluid

Boiling point values correspond approximately to those shown in the table below.

1. The wet boiling point (high water content) is the reference temperature used to determine when brake fluid replacement is required.
2. The dry boiling point (no water content) is the reference temperature for new brake fluid.
3. Tester accuracy: ±5%

Thermocouple (K-Type)

1. Uses a K-Type thermocouple.
2. Measurement range: -60°C to 500°C ± (1% + 3 digits)
3. Measurement deviation: -20°C to 500°C ± (1% + 3 digits)

Brake Fluid Testing

1. Battery voltage must be between 12 V and 13 V.
2. Before every measurement, ensure that the crocodile clips are connected to the vehicle battery with the correct polarity.
3. When the device is connected to the vehicle battery, it powers on automatically. The default startup mode is Function A. If Function B is displayed, press and hold the °C / °F button for 3 seconds to switch back to Function A. The letter "A" should appear on the LCD display.
4. Both brake fluid electrodes must be fully immersed in the brake fluid. Ensure that the fluid level is above the "Minimum Brake Fluid Level" mark on the measuring cup.
5. Press and hold the Start button to begin testing the brake fluid. Keep the brake fluid test probe in a vertical position throughout the test.
6. If "WAIT COOL" appears on the LCD display, allow the heating wire to cool down before performing the next test.
7. The user may use the brake fluid pipette to transfer a sample of brake fluid into the measuring cup for testing.

Caution

• After testing, wait at least 3 seconds for the heating wire to cool down before removing the test probe from the brake fluid.
• Avoid impacts or shocks to the test probe, especially immediately after testing.
• If the tester has not been used for an extended period, residue from previous tests may remain on the sensor and affect measurement accuracy. Perform a second test to obtain a more accurate reading.
• Shake or stir the brake fluid before taking a sample for boiling point testing.

Temperature Measurement Using Thermocouple

1. Connect the device to the vehicle battery. If Function A is active, press and hold the °C / °F button for 3 seconds to switch to Function B. The letter "B" will appear on the LCD display.
2. Connect the K-Type thermocouple to the tester to begin temperature measurement.
3. During Function B, if the K-Type thermocouple is not connected or if the measured temperature exceeds 500°C, "Hi" will appear on the LCD display.
4. During Function B, if the measured temperature is below -60°C, "Lo" will appear on the LCD display.