DETROIT — More and more car buyers want to bring their personal electronic devices with them on the road.

But getting things such as cell phones, music players and navigation systems to work in concert with a vehicle's accessory systems is proving a big challenge for suppliers and auto makers, a Microsoft Corp. executive says.

Speaking here on a panel on trends in telematics and navigation systems at the 2007 Ward's Auto Interiors Show, Velle Kolde, product manager for Microsoft's Windows Automotive Unit, says more effort is needed to ensure portable electronics are fit for the automotive environment.

“We think the No.1 killer app is connecting the phone to the car,” Kolde says. “In the surveys we've done, it is by far what consumers want most.”

The problem, he says, is that people who purchase cars and cell phones with Bluetooth technology, designed to allow the two to interact wirelessly for hands-free calling, find the devices don't always perform as billed.

“People say, ‘I have Bluetooth in my car, but it doesn't work with my phone,’” Kolde says. “That's because there's no de facto standard implementation to test against. Everything works fine separately but (may not when put together).”

The reality is most portable electronics developers don't pay much attention to designing with automobile interaction in mind, he says.

“It's just not a core scenario for the device manufacturers,” Kolde says. “They're looking at designing for low cost and a long battery life. Integrating with a car is not a high priority.”

In addition to cell phone use, Kolde says Microsoft surveys show consumers increasingly want to be able to play music from their iPods or MP3 players through the vehicle's sound system using wireless Bluetooth connectivity.

A more seamless integration of portable navigation and vehicle systems also is on the consumer wish list, he says.

“It's surprising to me that integration is not a core scenario (for personal electronics developers),” Kolde adds. “People want to talk on their phones safely in their cars. In the car is the No.1 or No.2 place where most people listen to music. For many people, it's where they have their best sound system.”

Kolde says Microsoft spends about 4% of its engineering time “making cool stuff,” with the remaining 96% is allocated to “making sure it works with everything.”

Also causing difficulties is the disparate lifecycles between automobiles and portable electronics, four years or more for the former and just 18 months for the latter.

However, the situation is improving. Kolde says in the last six months more cell phone manufacturers are coming to Microsoft in advance of launch to help them ensure new phones are compatible with other systems.

“Progress is being made, but a lot more could be happening to bring this up in priority,” he says. “The more influence car makers can put on these companies, the faster we can move.”

Kolde says ensuring automotive electronics architectures are designed to accommodate software upgrades will solve the disparate lifecycle issue.

Such is the case with Ford Motor Co.'s upcoming Sync system, which is run by an automotive version of Microsoft's Windows operating system. Sync will debut on the '08 Focus and eventually roll out to 11 other models. It allows users to access mobile phones or digital music players through voice commands.

Kolde says Microsoft will make similar software available to other auto makers worldwide beginning in December.