Knowledge Hub
Plain-English explainers on OBD2 diagnostics: what the terms mean, how the tools actually work, and what to check before you buy.
OBD2 Fundamentals
Start here if you're new to scan tools: what OBD2 is, how codes and live data work, and how to use a scanner safely.
What Is OBD2 and How Does an OBD2 Scanner Work?
When the Check Engine light comes on, your car usually knows more about the problem than the dashboard tells you.…
Read the Article
OBD2 Codes Explained: How to Read Diagnostic Trouble Codes
You connect an OBD2 scanner and see something like P0300, P0420 or P0171. Now what? Those five-character messages are Diagnostic…
Read the Article
How to Use an OBD2 Scanner: Step-by-Step Guide
The physical part of using an OBD2 scanner is usually easy. Find the diagnostic port. Plug in the tool. Establish…
Read the Article
How to Read OBD2 Live Data: PIDs, Fuel Trims, O2 Sensors and More
An OBD2 trouble code tells you that the vehicle detected a problem or condition. Live data lets you watch supported…
Read the ArticleScanner Capabilities
What "bidirectional," "full-system," and "coding" actually mean on a spec sheet.
What Is Bidirectional Control on a Scan Tool? Active Tests Explained
A basic scan tool asks the vehicle for information. A bidirectional scan tool can also ask a supported control module…
Read the Article
What Does Full-System Diagnostics Mean on a Scan Tool?
A basic OBD2 scanner may tell you why the Check Engine light is on. But what if the warning light…
Read the Article
ECU Coding vs Programming vs Adaptation: What’s the Difference?
A scan tool product page says: ECU Coding. Another says: ECU Programming. A third lists: Coding, Adaptation, Relearn and J2534…
Read the ArticleCompatibility & Ownership
Will a scanner actually work with your car, what format fits you, and what it really costs to own.
Will Any OBD2 Scanner Work With My Car? OBD2 Compatibility Explained
No, not in the sense most buyers mean. If your vehicle is OBD2 compliant, a compatible generic scanner can usually…
Read the Article
Bluetooth vs Standalone OBD2 Scanners: Which Type Is Right for You?
A Bluetooth OBD2 scanner uses a phone, tablet or computer as much of its user interface. A standalone scanner has…
Read the Article
OBD2 Scanner Subscriptions Explained: Updates, Renewals and the Real Cost of Ownership
An OBD2 scanner can cost $50, $500 or several thousand dollars. But the price on the box may not be…
Read the Article
How Much Should You Spend on an OBD2 Scanner?
You can buy an OBD2 scanner for less than the cost of a tank of gas. You can also spend…
Read the ArticlePractical Diagnostics
What to do with a trouble code, why a scanner won't connect, and how OBD2's modes and code ranges actually work.
Can an OBD2 Scanner Tell You Exactly What’s Wrong With Your Car?
Usually, no. An OBD2 scanner can tell you what the vehicle’s diagnostic system detected. That can be extremely useful. It…
Read the Article
What to Do After Your OBD2 Scanner Finds a Trouble Code
Your scanner has found a trouble code. Do not immediately clear it. And do not immediately buy the part whose…
Read the Article
The 10 OBD2 Modes Explained: Mode 01 to Mode 0A
Plug in an OBD2 scanner and you may see terms such as Mode 01, Mode 03, Mode 06 or Mode…
Read the Article
Generic vs Manufacturer-Specific OBD2 Codes: What’s the Difference?
Your scanner finds: P0301. On many vehicles, that code has a standardized meaning. Then it finds another code and displays:…
Read the Article
Why Won’t My OBD2 Scanner Connect to My Car? Troubleshooting Guide
Your OBD2 scanner is plugged in. But it says: No Communication. Linking Error. Unable to Connect. Or your Bluetooth adapter…
Read the ArticleAdvanced Protocols
The modern communication technologies behind late-model vehicle diagnostics.
CAN FD Explained: Why It Matters for Modern OBD2 Scanners
A scanner specification says: CAN FD Supported. Another scanner does not mention CAN FD at all. Does that mean the…
Read the Article
DoIP Explained: Why Modern Scan Tools Use Ethernet
A modern scan tool specification may list DoIP next to CAN FD, J2534, ECU Coding and Bidirectional Control. It is…
Read the ArticleMore From the Knowledge Hub
OBD2 vs OBD1: What Is the Difference and Does It Matter?
Why 1996 is the cutoff year that decides whether any OBD2 scanner will work on your vehicle.
Read the Article
Can an OBD2 Scanner Damage My Car?
Bi-directional control is what separates a diagnostic tool from a repair tool: here's what it actually does.
Read the Article