2D symbology, now required by GM, can prevent recalls Bar codes are not sexy, but the auto industry would stumble terribly without them. Cars could be built with the wrong colored seats - or no seats at all. There would be so many recalls that automakers would have to start paying dealers for franchises. The build-to-order thing? Forget it.

The bar code is ubiquitous. You'd have to watch Little House on the Prairie reruns to find a grocery store that doesn't use bar code scanners today.

The auto industry has used bar codes for nearly 20 years to simplify shipping, quality control and inventory management. They arrived along with electronic data interchange (EDI), the communication network that suppliers and automakers use to transmit purchase orders for parts.

When a supplier fills an order, it sends an EDI transmission ahead of the shipment so the customer knows what's coming and when. When the crate arrives, the folks in receiving, with EDI printout in hand, can scan the bar code to make sure it's the right package.

The Automotive Industry Action Group was formed in the 1982 to develop a common standard by which all suppliers and automakers could produce the symbols.

Now there's a new type of two-dimensional bar code that the auto industry is beginning to use in replacing the simple linear bar code familiar on canned goods.

As of Jan. 1, General Motors Corp. requires thousands of Tier 1 suppliers to use the 2D bar codes. Those who don't will get a quality "black mark" on their records. Some Tier 1s are resisting because of the cost of entry, which can be thousands of dollars per plant. Automakers around the world also are considering a global standard for 2D bar codes.

The move to 2D "symbology," a tool for more complete error-proofing, could help prevent future vehicle recalls, says Eric Freeburg, automotive industry executive with bar coding giant Intermec Technologies Corp.

The system was created to encode a lot more information in a smaller space. The new code takes various forms. Sometimes it has a dot in the middle, surrounded by a series of hexagons, or it may look like a contorted checkerboard.

The old linear code was applied on a sticker - one that usually didn't stick well to oily auto parts. The 2D symbol can be applied easily to every single part, if necessary, through innovative laser etching, chemical etching, peening or molding.

With every part labeled, automated digital cameras can be mounted along assembly lines. As the vehicle rolls by, it can scan automatically for the correct part. If it isn't found, assemblers are quickly notified.

That automated system already works with the old, linear bar codes for big, cumbersome parts like seats, headliners and bumpers. With 2D, the industry can use the codes on much smaller parts.

"With large parts, you don't usually have a problem putting the wrong part in the car - like the wrong seat. Occasionally the wrong engine gets in, but it's rare," Mr. Freeburg says. "But the components making up the part - there lies the problem."

He refers to a spark plug, which needs the proper gap for an engine to run properly. The human eye cannot tell if a spark plug is properly gapped, but a 2D bar code etched into the plug can eliminate any guesswork.

A 2D bar code can provide a lot more information about that spark plug: where and when it was produced, when it was shipped, what materials were used, job number. The possibilities for parts tracking are endless.

This is the type of traceable information that automakers are increasingly requesting of suppliers. Each piece of information requires a separate bar code with the old linear format, and suppliers say they can only cram about eight bar codes on a standard 4-by-6 in. (10-by-15 mm) shipping label, Mr. Freeburg says. There isn't room for any more. With the new format, one 2D bar code can contain multiple bits of information.

What angers many suppliers, Mr. Freeburg says, is that they have to provide more and more bar code information, yet the majority of bar codes on supplier shipments never get scanned on the OEM receiving dock - partly due to labor agreements and OEMs being slow to automate. OEMs generally assume the supplier's EDI transmission is accurate and complete.

Still, errors get through - errors that could be avoided if OEMs scanned bar codes. At least once a week at a Big Three plant, Mr. Freeburg says, an assembly line is disrupted because workers got the wrong parts.

"Sometimes they don't get to the recall stage, but cost of manufacture definitely could be saved," he says.