WASHINGTON -- Millions of vehicles could have malfunctioning electronic stability systems if drivers have customized their vehicles with add-on parts and accessories, a trade association says.
The Las Vegas-based Specialty Equipment Market Association, or SEMA, says the National Highway Transportation Safety Administration's proposal to mandate that all vehicles be equipped with the anti-rollover technology could prevent owners from customizing their cars and trucks or make the stability system inoperative. SEMA and NHTSA officials recently met to discuss the issue.
The association worries that the rule will not ensure that the safety systems are compatible when other equipment is added before or after a vehicle is sold, Stephen McDonald, SEMA's vice president of government affairs, said in a letter Thursday to NHTSA.
"This situation could translate into millions of cars having ESC systems that do not work properly or motorists being denied the opportunity to install aftermarket equipment on their vehicle," McDonald wrote.
About 40 percent of cars and trucks now on the road have electronic stability control, or ESC.
NHTSA says its proposal to require the technology in all vehicles by 2012 could save up to 10,600 lives a year and eliminate 80 percent of single-vehicle rollovers. It expects to issue a final rule by April.
The issue is emerging as stability control is becoming a popular safety feature among consumers and customizing vehicles has become big business.
According to the Specialty Equipment Market Association, known as SEMA, Americans spend about $35 billion annually on modifying and customizing their vehicles with special tires, wheels, suspension systems and other parts.
NHTSA spokesman Rae Tyson said Friday the agency is reviewing SEMA's concerns.
"We take any comment to a proposed rulemaking seriously and we'll certainly take it into account," Tyson said.
One big issue is whether modifying a vehicle will activate the ESC warning light on the dashboard.
"The last thing dealers want is dissatisfied customers running in with the warning light on," said Doug Greehaus, director, of environment, health and safety for the National Automobile Dealers Association, who attended the meeting.
NHTSA wants "more evidence this is actually a problem," according to the federal agency's summary of the Jan. 10 meeting. But if a dealer installed equipment on a new car that made ESC inoperative, the vehicle would not meet safety standards, according to the summary.
McDonald said in an interview Friday that his group hopes to report back to NHTSA about the extent of the problem within 30 days.
"The challenge is to convince the agency of the extent of the issue, the types of the equipment, the types of safety concerns," he said.
"Some of the equipment that is being installed is indicating a problem. We're not sure how big the problem is or if it can be remedied quickly by a software modification."
One solution SEMA suggests is equipping ESC systems with "adaptive learning" components that sense if a vehicle has different tires, for instance, and adjusts accordingly. Auburn Hills-based Continental Automotive Systems, which produces about 40 percent of electronic stability control systems in North America -- said it doesn't consider the issue a major concern.
"If you build your own monster truck, you will very likely get an ESC warning light," said Philis Headley, chief engineer for advanced technologies at Continental.
But he added "it's hard to predict what people could possibly do to their vehicles and what impact that will have."
Headley said there are only a handful of issues to be decided before a final stability control rule is announced, including whether vehicles have to have ESC when traveling in reverse. Currently ESC systems typically don't work when vehicles are operating in reverse.
GM spokesman Alan Adler said changing tires "could give you a false ESC indicator on a hard turn," Adler said.
"We don't have a system to adapt for those things." GM offers some add-on parts that have been engineered to work with GM vehicles.
