J2534 reprogramming brings new opportunity for business

Everything you need to know about J2534 programming.

Time was, you fiddled and tinkered, then adjusted just so to get a car to perform properly. Back then, this art form built the reputation of many mechanics and the evolution of the technician. Then, in the 1980s, GM gave us our first taste of changing a vehicle’s powertrain programming, through PROM (Programmable Read Only Memory) replacements. How high-tech it seemed, at least at the time.

As technology marched on, it brought about a new frontier in changing a vehicle’s programming, and it’s based on a standard from the Society of Automotive Engineers. Known as J2534, the standard provides a gateway to imparting new logic into automotive control systems when their “thinking” is fundamentally flawed.

WHAT IS J2534?

The standard encompasses a “recommended practice for pass-thru vehicle programming.” Essentially, as the automakers moved towards reprogrammable control units, it created the in-service need to actually provide the reprogramming function. J2534 steps outside the boundaries of being manufacturer-specific, and ties into the original generic design goals of OBD II systems. With that said, both the EPA and the California Air Resources Board required all vehicle manufacturers to meet J2534 requirements, beginning with the 2004 model year.

With the technology in place on vehicles, it opened the window of opportunity for aftermarket tool providers to build suitable reprogramming equipment.

It’s important to note that the J2534 standard does not specify hardware types or arrangements for compliant equipment. These details are left to the manufacturers of the equipment to establish designs they think are best. However, reprogramming software from any vehicle manufacturer must be compatible with hardware supplied by any tool manufacturer.

A couple of variations to the original J2534 standard have evolved since the original. J2534-1 deals exclusively with reprogramming emissions-based control modules on 2004 and newer vehicles. J2534-2 evolved as a variant for reprogramming some vehicles prior to 2004, and for some controllers not related to emissions control.


The J2534 reprogramming equipment you should consider must be able to handle the specific types of vehicles and systems that you intend to service, both now and as far as you can forecast into the future.

The bottom line is, J2534 reprogramming is here now and you simply can’t repair today’s vehicles without its capabilities. If a vehicle is running a flawed program, you must reprogram to fix it the right way.


Because of some of the open aspects of J2534-compliant design, and the types of vehicles you may need to service, all equipment is not created equally. So, a little homework is in order to seek the best match for your needs.

The best place to start is at the website of the National Automotive Service Task Force (www.nastf.org). NASTF is a cooperative effort among the automotive service industry, the equipment and tool industry and automotive manufacturers to ensure that automotive service professionals have the information, training and tools needed to properly diagnose and repair today's high-tech vehicles.

Once on the site, click on “Tools Matrix” and then on the link next to “Reprogramming Status Summary.” You will then see a matrix of vehicle manufacturers with a column titled, “J2534 software and calibrations available.” This will show you where each specific vehicle manufacturer stands regarding its ability to reprogram with J2534.

To learn more about exact details for each manufacturer, go back and click on the “Tools Matrix” link. Then, click on the links in the table on the center of the page to see the specific reprogramming details for that vehicle line. Also note the link to the “Service Information Matrix Page,” which will take you to a page with reprogramming information.

This content continues onto the next page...

We Recommend