Scan Tool Triage

Scan Tool Triage

New scan tools can bridge the divide between a basic scan and high end scan tool.

Next time you get a vehicle in with a check engine light on, use the stopwatch function on your smartphone to see how long it takes to go from plugging in the tool to getting the codes for basic triage diagnostics.

Once you get an average time, use your shop’s hourly labor rate for diagnostic labor to put a price on that time. Any improvement to the time between plugging in to having the codes, drops to the bottom line.

The wrong tool can slow your progress. Stumbling through complicated menus, inputting VINs and waiting for the tool to connect is valuable time that could be spent diagnosing the problem. It gets even more frustrating when you have to wait for the tool’s operating system to update.

New scan tools can bridge the divide between a basic scan and high end scan tool.

How do you increase your efficiency for some driveability and malfunction indicator lamp (MIL) problems? The solution might be to simplify your initial core diagnostics.

Battery First

With today’s vehicles having up to 50 computers and 150 electrified devices, the battery is critical to the health of the vehicle. If a vehicle is brought in for a drivability problem or a check engine light, check the health of the battery with a capacitance testing tool. This type of tool can quickly analyze the condition of the battery and charging system.

If a battery is marginal, it will cause codes that you might not think are battery related. These problems and codes can crop up when electrical loads are put on the electrical system when the vehicle is starting and shutting down. These codes can include U- or loss of communication codes and in some cases cause key-off EVAP emissions testing to be stopped. By looking at the battery first, it can also confirm the condition of some power distribution modules that control the alternator.

Resolving a weak battery before trying to diagnosis any problem is not a waste of time for two reasons. First, it can prevent you from chasing your tail to diagnose codes or an intermittent problem. Second, it can keep the driver from being stranded with a dead battery.

Testing the battery as part of the initial inspection can keep you from going down a diagnostic rabbit hole. And, it can help you to sell more batteries. 

The Basics

In the beginning, basic or pocket scan tools were limited to generic P-codes and basic emissions information like readiness monitors. Code definitions had to be looked up in a printed manual or online. As computer memory became cheaper, more code definitions and make-specific information could be incorporated into the tool.

For under $300 you can get a basic scan tool that can handle a lot of initial diagnostic tasks. The advantage of these tools is not only the price, but also their speed thanks to their simplicity.

Most of them can pull generic codes a lot faster than a full-feature diagnostic tool. This is not because of better hardware, but because of minimal menus and solid-state memory. These tools work great as a first step in resolving misfire codes and catalytic efficiency codes so further testing visually or with a scope can be performed.

However, on diagnostic problems with body control, power distribution and ABS modules, these tools typically won’t be of much help. A basic scan tool might not be able to communicate to these modules due to how they interface with the OBD II connector or the type of protocols/language used by the manufacturer.


Modern vehicles have many modules that can store codes.

More expensive tools will have added functions like the ability to check emission monitor statuses, freeze-frame data and faster display rates of data.

Is using a basic scan tool “discount diagnostics?” No, because to use a basic scan tool requires more knowledge to be able to interpret that information. These can be the right tools that can help you focus your diagnostic skill in the right area or help you to select the appropriate next tool.

Full-Feature Scan Tools Fight Back

Full-feature scan tools are getting faster every day. By automating vehicle communication processes, a complete heath check of the various modules can be performed with a few clicks. This replaces navigating the menus for the various modules.

Another advantage of a full-feature scan tool is the ability to access repair information online. This can include videos, OE service information and real-world fix databases. Having the information in the bay can save you from making multiple trips to a computer in the front office.

 Both the right tool and the wrong tool depend just as much on the job as it does the price tag of the tool. Of course, any tool is only as good as the technician using it, but the  right tool can be a time machine that can get you from initial write-up to repair faster and more profitably.

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