Auto Service World
Feature   April 1, 2010   by Andrew Ross

A/C and J2534: Reflashing Isn’t Just for Driveability

There was a time when all an A/C service specialist needed was a good set of gauges, a propane torch, and good instincts. Those days are gone.

There was a time when all an A/C service specialist needed was a good set of gauges, a propane torch, and good instincts. Those days are gone.

Now, due to sophisticated information networks that control a car’s every move, diagnosing and repairing HVAC systems relies as much on scan tools and software as emissions control and driveability work do.

And it’s not just the elusive computer-related repairs at stake. Without reflash capability, you might be able to replace that blower motor but never get it to talk to the rest of the system. Until the car’s systems recognize it, it’s little more than a lump of metal and plastic.

With the new Canadian Automotive Service Information Standard (CASIS), slated to go into effect in May, Canadian technicians and shop owners are on the verge of getting unfettered access to repair information and reflash capabilities. CASIS is a comprehensive, voluntary agreement allowing the automotive aftermarket easy access to emission-and non-emission-related service information, diagnostic tools, and training information, similar to the standard established under NASTF in the U.S. While some automakers already provide access to the Canadian industry, some do not. In preparation for this, it is wise to be prepared with an understanding of issues surrounding reflashing.

Two key presentations during the recent Mobile Air Conditioning Society Worldwide Conference focused on the tools you need to get the job done, and offered some key differences that can best be described as the “OE or nothing” and “try before you buy” approach.

First, the session led by Peter Orlando, a trusted trainer by Carquest, among others, on which scan tool to buy revealed where his overall view lies. Notwithstanding what a shop may have on hand, Orlando made the point that you can forget about finding an aftermarket do-it-all tool.

“I can tell you that the days of the handheld scanner that does everything are gone.” He said the OE tool is the way to go — but which one? “You could spend months looking through the tools available. The easier question is to ask, what tool would I not buy?”

And that provides as good a jumping-off point as any for a discussion on the flash and reflash components in your in-bay maintenance arsenal. Reflash tools differ from scan tools in that they are not diagnostic devices; they are repair devices, essentially no different from an impact wrench, except that the part they are designed to work on is software (or more accurately, chip programming).

In his presentation, Delphi instructor Dave Hobbs walked attendees through the tool options available and the procedures for using them to the best effect. There is really only one thing for you to remember when shopping reflash tools, he said: the SAE J2534 standard.

One of the agreed-upon keys when reviewing which reflash boxes to consider is to look for the designation J2534-2, the important point being the addition of the “-2”, which denotes the most recent version of the SAE protocol for reflash.

Hobbs advised, “Go to the supplier and ask what protocol they support. If you are looking to buy, look for the ‘-2.'” (Note that in at least one case, however, there is an exception: older BMWs still follow the older J2534 standard.)

While there is a broad range of types, brands, and price/ quality levels in the marketplace to choose from, in general, Hobbs said, there are some things you need to have on hand to successfully launch into performing reflash work.

Of course, you need a J2354 device, but you will also need a scan tool that can support the reflash process and/or a decent late-model PC with, for example, a Pentium 600MHz chip, 1G of available hard drive, an open USB port, a graphics card, and a DVD-ROM drive (not CD). Hobbs said that if your computer is two years old or less, you’re fine, but not if it’s a Mac or a Netbook.

You also need a high-speed Internet connection in order to access the reflash data that you will be downloading to the vehicle’s ECU. “And a good reliable connection. Any interruption can turn a module into a doorstop, sometimes recoverable only by a reman centre or a manufacturer.”

Wireless connections can sometimes be interrupted by a larger vehicle in the bay, such as an RV, and even wired connections should be evaluated. “You may have a lot of [electromagnetic interference]; and I have found the Cat 6 [cables] to be more robust.”

Because the investment to get started in this field can range into the thousands of dollars, depending on what equipment you have on hand — along with the fact that there is a significant training process if you are to really make it work for your business — you need to build a business case, Hobbs observed. Although the investment and training can be a considerable barrier to some shops, it might present an opportunity for others.

“You may become the J-tool shop in your town,” he said, and be able to market that capability to other shops.

Of course, to command that position you need to have the expertise to maintain it.

“If you have a tech that doesn’t like to follow directions, you can forget reflashing. You need to read every single word of the directions.”

There is a learning curve on where to look for information as well.

“Some techs are under the impression that calibration updates have a TSB (technical service bulletin). The hands-on experts know that a whole lot — some say the majority — of calibration updates do not have TSBs.” The only way to check for calibration updates is to look for them in sometimes hard-to- find sections of manufacturers’ websites.

General Motors, for example, has an advisory category known as PI, for preliminary information. “What this is is a ‘secret’ TSB. Don’t go to Alldata or Mitchell for it. You have to go the manufacturer’s website.”

And for that, he added, you don’t even need a scan tool or a reflash tool, just access to the websites. The site is a great starting place, though the upcoming developments surrounding CASIS may change this for Canadian techs.

One final caution Hobbs offered was not to go reflashcrazy. It is not a cure-all, and could even cause more problems.

“One reason you don’t want to just reflash like you change socks is not to reflash over a new calibration. GM got so tired of having techs put new over new, they put a safeguard in.”

The reason you don’t want to do that, he explained, is that you lose all the adaptive relearns for the transmission, fuel trim, and other elements.

“And then you have the psychological issue of having the car run differently when the customer takes it.”

Working with reflash capabilities can be complex and the results are not always predictable, as revealed by the many examples offered by MACS show attendees. Ultimately, the best advice is to have a reliable source to go to when problems arise. Find a tool source that has knowledgeable, and available, tech support when you need it.

“Good support means they might be able to take control [of the process] over the Web,” Hobbs said. “Cars are complicated. Scanners can be quirky. Now add a PC!”

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