How to Test a Car Battery With the Autel Battery Tester, Step by Step

Follow our step-by-step guide to testing a car battery with the Autel battery tester, plus how to choose the right Autel model for your shop.

Updated 9 Sep 2026 4 min read 6 sections

To test a car battery with the Autel battery tester, switch everything off, clean the terminals, clip the red lead to positive and the black lead to negative, enter the battery type and rated cold cranking amps from the label, and start the test. The tester reports voltage, measured cranking amps and the battery’s state of health, then gives a pass, fail or charge and retest result. Below we walk through each step, explain what the readings mean, and cover which Autel tools include a battery test.

What an Autel battery tester does

A conductance battery tester sends a small signal through the battery and measures how easily it passes. From that, it estimates internal resistance and how many cold cranking amps (CCA) the battery can still deliver, then compares the result with the rating printed on the label. This tells you far more than a plain voltmeter, because a battery can show a healthy voltage at rest and still be too weak to start an engine on a cold morning.

AAA AUTO TOOL Autel MaxiCheck MX900 diagnostic tablet — Autel maxicheck mx900$488.99Image from the merchant

Autel offers battery testing in two ways. There are standalone handheld testers, such as the MaxiBAS BT608, that clip onto the battery posts. And some Autel diagnostic platforms can run battery and electrical tests through their software, usually with an Autel battery test accessory. If you already own a scanner such as the Autel MaxiCheck MX900 or the Autel MaxiSys Ultra S2, check its function list and accessory options before buying a separate tester.

How to test a car battery with the Autel battery tester

The steps below follow the general procedure for a handheld Autel tester. The menu names on a diagnostic tablet may differ, so follow your tool’s on-screen prompts and manual.

Step 1: Prepare the battery

Turn the ignition off and switch off lights, the radio and other accessories. Close the doors so interior lights go out. If the terminals are corroded, clean them with a wire brush first. A clean, tight connection is needed for an accurate reading. Wear eye protection when working near a battery.

Step 2: Connect the test clamps

Attach the red clamp to the positive terminal and the black clamp to the negative terminal. Make sure the clamp teeth bite onto clean metal. Most handheld testers power on from the battery once connected.

Step 3: Enter the battery details

The tester asks for:

Battery type: flooded, AGM, gel or EFB
Rating standard: CCA, EN, DIN, IEC, SAE or CA, as shown on the label
Rated capacity: the number printed next to that standard

Copy the values from the battery label exactly. Guessing the rating from the vehicle model can give a false result.

Step 4: Run the test

Start the test and wait for the result screen. It typically shows:

Voltage: the battery’s resting voltage
Measured CCA: compare this with the rated figure
State of health (SoH): how much of its original ability the battery keeps
State of charge (SoC): how full the battery is right now

Step 5: Read the verdict

You will usually see good, replace, or charge and retest. If the battery passes but the car still cranks slowly, test the starter and charging system next. Many battery testers can run those checks too.

Understanding the test results

Reading	What it usually means	Next step
Around 12.6 V or higher at rest	Fully charged	Check SoH and measured CCA for health
Around 12.4 V	Partly charged	Charge fully, then retest
Below 12.0 V	Deeply discharged	Charge slowly and retest; replace if it will not hold charge
Measured CCA well below rating	Battery has lost capacity	Plan a replacement, especially before winter
Charge and retest	Tester cannot judge health at this charge level	Charge fully and test again

Voltage alone is not enough. A battery can read 12.6 V at rest and still fail because of high internal resistance, which is why a conductance test is more useful than a voltmeter check.

Which Autel battery tester should you choose?

Dedicated battery testers

Autel’s standalone BT testers are small handheld units built only for battery, starting and charging tests. They suit anyone who wants a quick battery check without a full scan tool. Compare models on the maker’s pages for features such as app connection, printing and supported battery types.

Diagnostic tablets and scanners

AAA AUTO TOOL Autel Ultra S2 diagnostic scanner — Autel ultra s2$5,459.00Image from the merchant

The Autel MaxiSys Ultra S2 and the Autel MX900 are full diagnostic platforms for reading codes and running system tests. Whether they cover battery testing depends on the software and accessories, so check the product page. The Autel IM608, Autel IM508S and Autel MaxiIM KM100 are mainly key and immobilizer programming tools. A stable battery matters during key programming, so a separate battery check before the job is a good habit.

TPMS tools

The Autel MaxiTPMS TS508WF (also listed as the Autel TS508) is built for tire pressure sensor activation and programming. It is not a battery tester. If battery testing is your main need, choose a dedicated tester or a scanner that supports it.

Tips for accurate battery testing

Mind the temperature. Cold batteries read lower. Use the tester’s temperature setting if it has one.
Let surface charge settle. A battery that was just charged or driven can read high. Let it rest before testing, or follow the tester’s surface charge prompt.
Keep clamps clean. Dirty or corroded clamps add resistance and skew the reading.
Test in the car or out. Both work, as long as everything is switched off and the clamps sit on the posts, not on bolts or cable ends.
Save your results. If your tester connects to an app or printer, keep a record so you can see the battery change over time.

Autel lists its battery accessories on the Battery Service Tools page, and the MaxiBAS BT608 Battery & Electrical System Analyzer page has the maker’s own details on that model.

Where to buy an Autel battery tester

AAA AUTO TOOL sells Autel diagnostic tablets, key programmers and TPMS tools. Check each listing for what is in the box, which functions are included and the warranty terms before you order. For savings on your order, see the current AAA AUTO TOOL discount code.

Questions

How do I test a car battery with the Autel battery tester?

Switch off the ignition and accessories, clean the terminals, connect red to positive and black to negative, enter the battery type and rating from the label, then run the test and read the verdict.

Can I test a battery that is still in the car?

Yes. Make sure the ignition and all accessories are off and the clamps sit directly on the battery posts.

Does the Autel battery tester work on AGM batteries?

Autel testers let you pick the battery type during setup, including flooded, AGM, gel and EFB. Check your model's manual for the full list it supports.

How often should I test a car battery?

We suggest testing during routine maintenance, before winter, and any time the engine cranks slowly.

Can Autel tools also test the charging system?

Many battery testers can run starting and charging system tests after the battery test. For a diagnostic tablet, check the product page for the functions and accessories it supports.