1. Introduction
This user manual provides comprehensive instructions for the safe and effective operation, maintenance, and troubleshooting of your TESMEN TBF-200 Brake Fluid Tester. This high-precision device is designed to accurately measure the moisture content in various types of brake fluids, ensuring optimal vehicle safety and performance. It is compatible with DOT3, DOT4, and DOT5.1 brake fluids.
Regular testing of brake fluid is crucial as moisture absorption can significantly reduce the fluid's boiling point, leading to brake fade and compromised braking efficiency. The TESMEN TBF-200 helps you identify when brake fluid replacement is necessary.
2. Product Overview
The TESMEN TBF-200 Brake Fluid Tester is a compact and user-friendly tool equipped with advanced features for accurate brake fluid analysis.
Key Features:
- Efficient Measurement and Quick Readout: Digital display with tri-color backlight alarm system for quick conclusions based on displayed values (0%-4% measurement range).
- Corrosion-resistant and Clean: Features an 8.5-inch adjustable gooseneck metal probe for flexible operation and extended lifespan.
- Versatile and Feature-Rich: Compatible with DOT3, DOT4, and DOT5.1 brake fluids, includes a data hold function.
- Compact and Portable: Lightweight (0.15lb) with a convenient back clip for easy carrying.
Components:
- TESMEN TBF-200 Brake Fluid Tester Unit
- 8.5-inch Corrosion Resistance Gooseneck Probe
- Digital Display with Tri-Color Backlight
- Power Button (On/Off)
- Selection/Data Hold Button (S)
- Battery Compartment (for 2x AAA batteries)
- Custom Storage Pouch
- User Manual


3. Setup
Battery Installation:
- Unscrew the cap at the bottom of the tester unit to access the battery compartment.
- Insert two 1.5V AAA batteries, ensuring correct polarity (+/-). The batteries are included with your purchase.
- Securely screw the cap back onto the unit.

4. Operation
Powering On/Off:
- Press the Power button (
) to turn the tester on. The display will light up. - To turn off, press and hold the Power button for a few seconds. The device also features a 5-minute automatic shutdown to conserve battery life.
Selecting Brake Fluid Type:
- Press the Selection button (
) to cycle through DOT3, DOT4, and DOT5.1 fluid types. Ensure the selected type matches the brake fluid you are testing.
Performing a Test:
- Carefully remove the cap from your vehicle's brake fluid reservoir.
- Insert the gooseneck probe into the brake fluid, ensuring both metal electrodes at the tip are fully submerged.
- The tester will automatically display the moisture content percentage.
- To hold the current data on the screen, long press the Selection button (S). Press again to release.
- After testing, immediately remove the probe and securely replace the brake fluid reservoir cap.

Interpreting Results (Tri-Color Backlight Alarm):
- Green Backlight (0%-2% moisture): Indicates that the brake fluid is in good condition and safe for continued use.
- Yellow Backlight (2%-3% moisture): Suggests that the brake fluid is nearing its limit and should be considered for replacement soon.
- Red Backlight (3%+ moisture): Signals that the brake fluid is severely contaminated with moisture and requires immediate replacement to ensure braking safety.


5. Maintenance
Cleaning the Probe:
- After each use, clean the metal electrodes of the probe with a clean, dry cloth to remove any residual brake fluid.
- Ensure the probe is completely dry before storing the device.
Storage:
- For long-term storage, it is recommended to remove the AAA batteries from the unit to prevent potential corrosion.
- Store the TESMEN TBF-200 in its custom storage pouch in a cool, dry place, away from direct sunlight and extreme temperatures.

6. Troubleshooting
Common Issues:
- No Power: Check if batteries are correctly inserted and have sufficient charge. Replace if necessary.
- Inaccurate Readings: Ensure the probe electrodes are clean and fully submerged in the brake fluid. Verify that the correct DOT fluid type is selected on the device.
- No Reading: Confirm the probe is making proper contact with the fluid. Ensure the device is powered on.
If you encounter persistent issues not covered here, please refer to the detailed user manual included in the product packaging or contact TESMEN customer support.
7. Specifications
| Specification | Value |
|---|---|
| Product Dimensions | 8.5 x 3.74 x 1.57 inches |
| Item Model Number | TBF-200-BL |
| Batteries | 2 AAA batteries (included) |
| Measuring Range | 0% - 4% |
| Output Type | Digital |
| Probe Length | 8.5 inches (gooseneck) |
| Weight | 7.83 ounces |
8. Warranty and Support
The TESMEN TBF-200 Brake Fluid Tester comes with a 3-year limited warranty. This warranty covers repair of the unit free of charge, provided you have proof of purchase. The warranty does not cover replacement of the unit, only repair.
For technical support, warranty claims, or any inquiries regarding your TESMEN product, please refer to the contact information provided in your product's original user manual or visit the official TESMEN website.