LOS ANGELES -- A sign inside the Humming Motors auto repair shop says, "We do the worrying so you don't have to."
These days, owner David Baur spends a lot of time worrying in his full-service garage near downtown Los Angeles.
As cars become vastly more complicated than models made just a few years ago, Baur is often turning down jobs and referring customers to auto dealer shops. Like many other independent mechanics, he does not have the thousands of dollars to purchase the online manuals and specialized tools needed to fix the computer-controlled machines.
Baur says the dilemma has left customers with fewer options for repair work and given automakers an unfair advantage.
"When I was younger, I kept going until I solved the problem," the weary mechanic said as he wiped grease from his hands while taking a break. "Lately I find myself backing out. I'm more reluctant to take [on] complex jobs."
Access to repair information is at the heart of a debate over a congressional bill called the Right to Repair Act. Supporters of the proposal say automakers are trying to monopolize the parts and repair industry by only sharing crucial tools and data with their dealership shops. The bill, which has been sent to the House Committee on Energy and Commerce, would require automakers to provide all information to diagnose and service vehicles.
Automakers say they spend millions in research and development and aren't willing to give away their intellectual property. They say the auto parts and repair industry wants the bill passed so it can get patented information to make its own parts and sell them for less.
"Coke doesn't give away the recipe for Coke," said Charlie Territo, a spokesman for the Alliance of Automobile Manufacturers. "What this bill seeks to get is the recipe for Coke."
Many new vehicles come equipped with multiple computers controlling everything from the brakes to steering wheel, and automakers hold the key to diagnosing a vehicle's problem. In many instances, replacing a part requires reprogramming the computers -- a difficult task without the software codes or diagrams of the vehicle's electrical wires.
Mechanics say repair information gets constantly updated so they must know how to find answers amid the sometimes overwhelming amount of data. Keeping up with technology has become almost a part-time job and requires thousands of dollars to get the right tools and online manuals for each model.
"Doctors have it easy because the human body doesn't change model every year," said Paul Brow, owner of All-Car Specialists, a 30-year-old shop in suburban San Gabriel.
The technology wave has made even the simplest tasks difficult for some ill-equipped mechanics. Baur, for instance, said he couldn't turn off the "check tire pressure" light after fixing a 2008 Mercury Grand Marquis because he lacked the roughly $1,000 tool to reset the tire pressure monitor.
The customer said he has to visit the dealer shop to complete the job.
"The tires are fine, for some reason the light just stays on," Louis Ontiveros, 42, said. "I haven't had the time to deal with it."
Dealership shops may be reaping profits from the technological advancements. A study released in March by the Automotive Aftermarket Industry Association found vehicle repairs cost an average of 34 percent more at new car dealerships than at independent repair shops, resulting in $11.7 billion in additional costs for consumers annually.
The association, whose members include Autozone, Jiffy Lube and other companies that provide replacement parts and accessories, contend automakers want the bill rejected so they can continue charging consumers more money.
"You pay all this money for your car, you should be able to decide where to get it repaired," said Aaron Lowe, the association's vice president of government affairs.
Opponents of the bill counter that the information and tools to repair the vehicles are available to those willing to buy them. They say any mechanic who can't get what they're looking for can file a complaint with the National Automotive Service Task Force. The nonprofit takes the complaints to carmakers and tries to resolve them through a voluntary arbitration process. Of the 44 complaints filed last year, all were resolved, according to the organization.
The bill, introduced by Rep. Edolphus Towns, D-N.Y., has been stalled in the House committee since April but has attracted 51 co-sponsors. It's unclear when or if the committee will vote on the matter.
Not all independent mechanics want to see the proposal approved.
Donny Seyfer, owner of a repair shop in Wheat Ridge, Colo., said the bill gives the impression that mechanics are unable to fix cars unless Congress steps in.
"I am so upset they're out there telling my customers that I can't do my job," said Seyfer, who leads training classes for mechanics. He said the modern mechanic must take regular training classes and spend hours reading and networking with other mechanics to share the latest repair information.
Seyfer said mechanics can't afford to work on all types of cars because vehicles are increasingly built with unique specifications and require their own set of tools. Mechanics must specialize in a select number of models to stay competitive, he said.
Baur said specialization is a luxury he can't afford. He said he bought the garage 20 years ago from a former boss who serviced all kinds of cars.
"What are you going to do? Refuse service to the people who've been coming here all these years?" he said.
Carolyn Coquillette, owner of a 2-year-old shop in downtown San Francisco that specializes in hybrid vehicles, said she spends about $11,000 a year on diagnostic tools and subscriptions to online databases. She said she passes the cost down to the customer but can compete with dealer shops by offering better deals.
She said her shop offers another advantage: Her team of mechanics can modify technical features and convert the hybrids -- which are powered by battery and gasoline -- into plug-ins.
"Cars present a challenge to me," Coquillette said. "I can think it's a pain in my butt, or I can think this is why I'm paid to do this job."