Volvo Car Corp. sport-utility vehicles are being investigated by the U.S. for electronic faults that can cause the malfunctioning of the headlights and turn signals, which may raise the risk of a crash.

So far, the government isn't aware of any crashes resulting from the fault, but 21 owners of Volvo XC90 SUVs belonging to the 2004 and 2005 model years have filed a complaint, the National Highway Traffic Safety Administration said today on its website.

The defect isn't linked to crashes or injuries, NHTSA said. The malfunctions were experienced during both city and highway driving and manifested on 2004-2005 XC90 SUVs. NHTSA says that 93,487 vehicles are potentially impacted by the problem, according to the regulator. When the unit controlling the electronic parts was replaced, the flaws were corrected, the agency said, citing the complainants.

"We will provide all the information that NHTSA asks and we’ll work closely with the agency to make sure the issue is resolved," said James Hope, a U.S.-based Volvo spokesman.

The handling of the situation should be a simple process. Regulators say that simply replacing a bad control module is enough to set everything working again.

Volvo, a Swedish carmaker, is being bought by Zhejiang Geely Holding Group Co. from Ford Motor Co. for $1.8 billion in the biggest overseas purchase by a Chinese automaker.
Volvo in 2007 recalled its 2005 XC90s to inspect the batteries to ensure they didn't short circuit and cause fires.