DETROIT – Without well-managed integration and due diligence, the benefits of lighting programs can disappear in a flash, automotive suppliers warn.

Light-emitting diodes enable auto makers to introduce an endless array of shades and hues to vehicle interiors. But when multiple suppliers are involved in a program, and their respective components feature LED, there is increased potential for error.

“If your radio doesn’t match your HVAC (heating, ventilation, air conditioning) system, and your HVAC system doesn’t match your cluster, you’ve got a problem,” says Lenzy Petty Jr, product marketing manager for Osram GmbH, the industry’s leading supplier of LED technology.

Fortunately, the light bulb went on at Ford Motor Co., Petty tells a panel discussion at the 2008 Ward’s Auto Interiors Show here. The auto maker has appointed LED managers to work with suppliers and ensure seamless integration.

“It’s critical to get that right,” Peter Horbury, executive director-design for Ford’s Americas operations, tells Ward’s before his keynote address. “It’s like when you buy a stereo. You buy a bit from Denon (Co.), a bit from Pioneer (Electronics Inc.) – they all look mismatched.”

Petty and fellow panelist Robert Stewart of Lear Corp. credit the auto maker with advancing interior LED applications. The Ford Mustang has included a customizable instrument cluster since the car was redesigned for ’05.

Horbury says this feature, which enables consumers to choose from 125 lighting colors, will remain with Mustang and proliferate, in various configurations, across model lines. The all-new ’09 Ford Flex cross/utility vehicle offers customizable lighting in areas such as footwells and cupholders.

Execution also is key, Petty adds, so controls are a critical consideration. Some systems employ dials, others feature a “step process,” he says. “You press a button and each time you get a different color.”

Petty cites changeable LED lighting as a major interior trend, and panelist Royce Channey, senior industrial designer with Visteon Corp., notes its availability in vehicles ranging from high-end luxury cars to entry-level Scion-brand vehicles.

“It is growing from both ends of the spectrum,” Channey says.

But adopting the technology is not as easy as throwing a light switch, says Lear’s Stewart, program management director-hybrid, power electronics, wireless and amplifiers. Auto makers and suppliers are well-advised to check first with their legal departments.

“For tri-color LEDs that vary in color, anything that’s programmable, anything that’s selectable, Color Kinetics has a very strong patent in place,” Stewart warns.

Color Kinetics is a division of Philips Solid-State Lighting Solutions.

Meanwhile, the next bright idea on the horizon involves electro-luminescence, Stewart says. Because the light is transmitted through a film instead of a tube or bulb, auto makers will realize greater design flexibility.

“You can cut contours, you can mold it over things,” Stewart says. “Structures glow with it.”

Durability testing is under way, he adds, but applications for production vehicles are at least five years away.

“It’s being looked at very closely by the OEMS,” Stewart adds.

emayne@wardsauto.com