Diagnostic Tools

Diagnostic tools at Global Swanky include OBD2 scanners and code readers, car battery and relay testers, endoscope inspection cameras, multimeters, metal detectors and meters for water, air and moisture. Prices start at $11.99, with free US shipping.

On this page

1. What Are Diagnostic Tools?
2. What's in Our Diagnostic Tools Range?
3. How OBD2 Works
4. OBD2 Scanners and Code Readers
5. Car Electrical and Battery Testers
6. Inspection Cameras and Thermal Imaging
7. Multimeters and Electrical Testers
8. Home and Environmental Meters
9. Detectors
10. Understanding the Check Engine Light
11. How to Use an OBD2 Scanner
12. How to Choose Diagnostic Tools
13. Safety When Diagnosing
14. Caring for Your Tools
15. Diagnostic Tools for Different Users
16. How Much Do Diagnostic Tools Cost?
17. Shipping, Returns and Support
18. Diagnostic Tools FAQs
19. Find the Right Diagnostic Tools

What Are Diagnostic Tools?

Diagnostic tools are devices that test, measure or read data so you can find the cause of a problem before you fix it. For cars, they range from simple test lights to scanners that read fault codes from the engine computer.

The same idea applies around the home and workshop: multimeters check electrical circuits, endoscopes look inside tight spaces, and meters measure moisture, air quality or water quality.

Why diagnose first

Finding the cause first saves time and money, because good diagnostic tools help you replace only what's actually faulty.

For DIYers and professionals

Simple code readers and testers are diagnostic tools that suit car owners, while advanced scanners with live data and service functions suit enthusiasts and mechanics.

What's in Our Diagnostic Tools Range?

The range lists 90 products, all in stock when we updated this page on October 7, 2026. Prices run from $11.99 to $919.32, with a median starting price of $33.44.

Counts come from product titles on October 7, 2026. Check vehicle compatibility and what's included on each listing.

How OBD2 Works

OBD2, or On-Board Diagnostics II, is the self-checking system built into modern cars, and it's what most car diagnostic tools connect to.

Which cars have OBD2

According to the California Air Resources Board, all 1996 and newer gasoline passenger cars and trucks, and 1997 and newer diesel cars and trucks, must have OBD II systems.

What it does

The car's computer monitors the engine and emissions systems. When it spots a problem, it stores a diagnostic trouble code and may turn on the Check Engine light.

Where the port is

The 16-pin OBD2 port is usually under the dashboard on the driver's side, near the steering column.

Reading trouble codes

Codes start with a letter: P for powertrain, B for body, C for chassis and U for network. The numbers that follow point to the specific system.

OBD2 Scanners and Code Readers

Scanners are the most popular diagnostic tools for drivers.

Basic code readers

Code readers show and clear engine trouble codes. They're affordable and easy to use. The OBD2 Diagnostic Trouble Code Reader for Car Engine System Checks costs $41.23.

Bluetooth and Wi-Fi scanners

Wireless adapters plug into the port and send data to a phone app. The OBD2 Car Engine Code Reader with Bluetooth 5.1 Dual Mode costs $22.14.

Scanners with live data

Live data shows sensor readings such as engine speed, coolant temperature and oxygen sensor values while the engine runs. The OBD2 Diagnostic Scanner with Live Data and Portable Carrying Case costs $105.66.

Advanced scanners

Advanced tools read more systems, such as ABS brakes and SRS airbags, and include service functions like oil light resets. The OBD2 Car Diagnostic Scanner with ABS SRS and 5 Service Functions costs $304.78.

Brand-specific scanners

Some scanners focus on one car brand for deeper access to its systems. Check that your model is supported.

Scanner and gauge combos

Some kits pair a scanner with a dashboard display. The KW850 OBD2 Scanner + KW206 Car HUD Gauge costs $62.15.

Car Electrical and Battery Testers

Electrical faults are common, and simple diagnostic tools like testers make them easier to find.

Battery testers

Battery testers check voltage, cranking power and charging. The 12V Car Battery Tester 100-2000CCA Load & Charging Analyzer Tool costs $38.67.

Relay testers

Relay testers check 4-pin and 5-pin automotive relays without guesswork. The Small Automotive Relay Tester 12V Portable Car Diagnostic Tool costs $26.38.

Circuit testers and test lights

Test lights and circuit testers show whether a wire has power. The Car Test Pencil 6-24V for Modification and Maintenance Checks costs $11.99.

Tachometers

Digital tachometers measure engine speed for tuning and repair.

Inspection Cameras and Thermal Imaging

Inspection cameras are visual diagnostic tools that let you see what's hidden.

Endoscope cameras

Endoscopes slide a small camera into engines, walls and pipes. The Android Endoscope Camera with Waterproof Dual Diameter Probes costs $24.77.

Automotive inspection cameras

The HD Automotive Endoscope Camera for Car Repair and Inspection costs $28.18 and helps you check hard-to-reach engine areas.

Thermal imaging

Thermal cameras show heat patterns, which helps find overheating parts, electrical hot spots and draughts. The Thermal Imaging Camera for Electrical, HVAC, and Home Inspections costs $323.08.

Multimeters and Electrical Testers

Multimeters are essential diagnostic tools for electrical work.

What a multimeter measures

Multimeters measure voltage, current and resistance, and many add continuity and diode tests. The Digital Multimeter 830B High Precision Voltage Tester costs $23.18.

Network cable testers

Cable testers check Ethernet and phone wiring.

Signal meters

Satellite finders help align dishes for the strongest signal.

Home and Environmental Meters

Not all diagnostic tools are for cars.

Water quality meters

pH and TDS meters check drinking water, aquariums and hydroponics. The Water Quality Testing Pen for pH TDS and Drinking Water Checks costs $25.61.

Air quality monitors

CO2 and air quality monitors track indoor air, temperature and humidity. The 5-in-1 Air Quality Detector for CO2, Temperature & Humidity Monitoring costs $31.59.

Moisture meters

Moisture meters check wood and walls for damp. The Digital Moisture Meter for Wood, Walls, and Building Materials costs $28.70.

Coating thickness gauges

Paint thickness gauges help check car bodywork for repairs.

Weather and wind meters

Anemometers and weather stations measure wind, rain and temperature.

Detectors

Detectors are diagnostic tools that help you find what you can't see.

Metal detectors

Handheld and disc metal detectors suit treasure hunting, security checks and finding pipes. The Waterproof Metal Detector with 3 Sensitivity Modes and LED costs $41.85.

Hidden camera detectors

Detectors scan hotel rooms and rentals for hidden lenses and signals.

Understanding the Check Engine Light

The Check Engine light is your car's way of reporting a stored fault that diagnostic tools can read.

Steady light

A steady light means the computer has found a problem. Read the code soon and arrange a repair.

Flashing light

According to the Nevada DMV, you shouldn't drive if the Check Engine light is flashing.

Loose gas cap

A loose or broken gas cap can turn the light on, so check it first.

Clearing codes

Clearing a code turns the light off, but the fault returns if it isn't fixed.

How to Use an OBD2 Scanner

Follow these steps to read your car's codes:

1. Turn the engine off and find the OBD2 port under the dashboard.
2. Plug in the scanner or wireless adapter.
3. Turn the ignition on, or start the engine if the instructions say so.
4. Connect the app if you're using a Bluetooth or Wi-Fi adapter.
5. Read and note the trouble codes.
6. Look up what each code means and check related parts.
7. Fix the cause, then clear the codes and check the light stays off.

How to Choose Diagnostic Tools

Follow these checks when buying diagnostic tools:

• Match the task: code reading, live data, electrical testing or inspection.
• Check compatibility with your vehicle's make, model and year.
• Choose the connection: wired handheld, Bluetooth or Wi-Fi.
• Check app support for iPhone or Android.
• Look for extra functions such as ABS, SRS and service resets if you need them.
• Consider updates and whether software updates are free.

Safety When Diagnosing

• Work in a ventilated area if the engine is running, and never in a closed garage.
• Apply the parking brake and keep hands clear of moving parts.
• Disconnect the battery before working on electrical systems unless testing requires power.
• Use rated multimeter leads and the correct setting for each test.
• Ask a professional for brake, airbag and high-voltage hybrid or electric vehicle systems.

Caring for Your Tools

• Store scanners and meters in their cases.
• Keep cables untangled and connectors clean.
• Remove batteries from meters stored for long periods.
• Clean camera lenses gently after inspections.
• Update scanner software when updates are available.

Diagnostic Tools for Different Users

The best diagnostic tools depend on who's using them.

Everyday drivers

A Bluetooth code reader and a battery tester cover most needs, from Check Engine lights to slow starts.

DIY enthusiasts

Scanners with live data, a multimeter, relay tester and endoscope help with deeper repairs.

Used car buyers

A code reader and paint thickness gauge help you check a car's history and bodywork before buying.

Homeowners

Moisture meters, air quality monitors and endoscopes help find damp, poor ventilation and hidden pipe problems.

How Much Do Diagnostic Tools Cost?

Our diagnostic tools range from $11.99 to $919.32. Of 90 listings, 2 start under $20, 61 start between $20 and $50, 17 start between $50 and $100, 5 start between $100 and $300, and 5 start at $300 or more.

Here's what each price band typically buys:

• Under $50: Bluetooth code readers, battery and relay testers, multimeters and endoscopes.
• $50 to $100: scanners with screens, combo kits and metal detectors.
• $100 to $300: scanners with live data, brand-specific tools and weather stations.
• $300 and up: advanced scanners with ABS, SRS and service functions, and thermal cameras.

Standard US shipping is free on every order.

Shipping, Returns and Support

We ship diagnostic tools to US addresses only, and standard shipping is free. Most orders arrive within 6 to 32 business days, and you can track your order once it ships.

Returns are accepted within 30 days of delivery if the item is new, unused and in its original packaging, with no restocking fee. Read the full terms in our return policy, and contact our support team if your order arrives damaged.

Diagnostic Tools FAQs

Will an OBD2 scanner work on my car?

Most likely, if it's a 1996 or newer gasoline car or truck sold in the US, or a 1997 or newer diesel. Check the listing for supported protocols, and confirm brand-specific features if you need more than engine codes. The port is usually under the dashboard.

What's the difference between a code reader and a scanner?

Code readers are basic diagnostic tools that read and clear engine trouble codes. Scanners usually add live data, freeze frame data and sometimes extra systems such as ABS and airbags, plus service functions for maintenance tasks. Choose based on how much detail you need.

Can I clear the Check Engine light myself?

Yes, most scanners and other OBD2 diagnostic tools can clear codes. But the light will come back if the fault isn't repaired, so read and note the code, fix the cause, then clear it and check the light stays off.

Do Bluetooth OBD2 adapters drain the battery?

Some adapters draw a small amount of power while plugged in. If you don't drive often, unplug the adapter after use to avoid draining the battery over time, especially in cold weather when batteries are weaker. Some adapters have a sleep mode that reduces this.

What does a car battery tester check?

Battery testers check voltage, cold cranking amps and often the charging system. They help you tell whether a slow start is caused by the battery, the alternator or something else, which saves replacing a good battery. Test with the engine off and the car rested for best accuracy.

What can an endoscope camera be used for?

Endoscopes inspect hard-to-reach spaces such as engine cylinders, pipes, drains, walls and behind panels. Waterproof probes suit plumbing, and phone-compatible models let you view and save images on your screen. They're versatile diagnostic tools for home and car, so check probe length before buying.

Do I need a multimeter for car repairs?

A multimeter is one of the most useful diagnostic tools for electrical problems. It checks battery voltage, fuses, wiring continuity and sensors, helping you find faults that a code reader can't pinpoint. Learn the basic settings before testing live circuits.

Is it safe to drive with the Check Engine light on?

A steady light means you should get the car checked soon. A flashing light can indicate a serious problem, and the Nevada DMV advises not driving when it flashes. Stop safely and seek help from a mechanic or roadside service.

Do scanners work on electric cars?

Many basic OBD2 diagnostic tools read some data from hybrids and electric cars, but high-voltage systems need specialist equipment and training. Leave high-voltage diagnostics and repairs to qualified technicians with insulated equipment. Check each listing for hybrid and EV support before ordering.

How accurate are home water and air meters?

Home meters give useful quick readings for everyday checks. Calibrate them as instructed, replace probes when worn, and use a certified lab test if you need precise results for drinking water or health concerns. Keep them clean and store them dry.

How long does shipping take?

Most orders arrive within 6 to 32 business days of being placed. That covers 1 to 2 business days of handling and 5 to 30 business days in transit. Standard shipping is free on every order, and we currently ship to US addresses only.

Can I return a diagnostic tool?

Yes, within 30 days of delivery, if the item is new, unused and in its original packaging. Email support@globalswanky.com with your order number, the product name and the reason for the return, then wait for return instructions. There's no restocking fee.

Find the Right Diagnostic Tools

Choosing diagnostic tools comes down to three checks: the job you need to do, compatibility with your vehicle or system, and the features you'll actually use. A Bluetooth OBD2 code reader is the easiest place to start for most drivers.

Ready to choose? Scroll up to the product grid, or browse our tools and hardware, power tools and car LED lights collections.