BT-171 Multifunctional 12V Battery Tester with LED Display, Reverse Connection Alert & Overload Protection – Auto Repair & Electrician Tool for Accurate Voltage Testing, Car Battery Tester

Keep your car battery and charging system in top condition with the BT-171 Multifunctional 12V Battery Tester—a practical diagnostic tool for accurate voltage testing and quick battery health checks. Whether you’re an auto technician, electrician, or everyday driver, this tester helps you detect battery problems early, preventing unexpected breakdowns and improving reliability.

The BT-171 features a bright LED digital display that clearly shows the battery voltage reading. It also includes easy-to-read status bars that indicate battery condition such as FULL, MEDIUM, LOW, DEAD, and EMPTY, helping you understand at a glance whether the battery needs charging, maintenance, or replacement.

In addition, it can help evaluate your vehicle’s charging system (generator/alternator state)—so you can confirm whether your alternator is charging properly when the engine is running. For safer use, the tester is designed with a reverse connection alert to warn you if you connect the clamps the wrong way, and overload protection to improve durability and prevent damage.

Perfect for use on cars, SUVs, van, pickup trucks, motorcycles (12V systems), inverters, and other 12V battery setups, this compact tool is a must-have for any workshop or home garage.

Key Features

Model: BT-171

Voltage Range: 12V battery systems

Display: LED digital voltage display + status indicator lights

Functions: Battery voltage test, battery condition indication, charging/alternator status check

Safety: Reverse connection alert + overload protection

Use Case: Auto repair, electrician troubleshooting, routine battery checks

Specifications (Approx.)

Product Size: 120mm (height) x 70mm (width)

Thickness: 19mm

Color: Black

Power Source: Powered by the battery being tested (no extra battery required)

How to Use

Connect Red clamp to (+) and Black clamp to (-) terminal.

Read the voltage on the digital display.

Check the indicator lights to understand the battery state and charging status.

If “Reverse” indicator lights up, disconnect and reconnect correctly.