Just as Toyota was putting its quality woes in its rearview mirror, the Japanese automaker hit another mechanical snafu forcing its biggest worldwide recall yet.
On Wednesday, Toyota announced it would be recalling 7.4 million vehicles, some 2.5 million of them in the United States.
The problem: the driver's power-window master switch can short-circuit and catch fire. Toyota has documented 42 cases where a fire or flame was reported in the switch mechanism or in the car door. In nine cases, Toyota says, there were minor injuries, none involving medical care. No crashes have been linked to the defect.
The cars and model years involved in the Toyota recall are:
• 2007-08 Yaris
• 2007-09 RAV4
• 2007-09 Tundra
• 2007-09 Camry
• 2007-09 Camry Hybrid
• 2008-09 Scion xD
• 2008-09 Scion xB
• 2008-09 Sequoia
• 2008 Highlander
• 2008 Highlander Hybrid
• 2009 Corolla
• 2009 Matrix
Starting late this month, Toyota will begin notifying affected owners of the recall, urging them to have a dealer inspect and repair the switch mechanism using a special fluorine grease.
Warning signs that there may be a problem are a sticky or "notchy" feel when a driver engages any of the power-window switches. If this does occur, contact a dealer. Don't try to lubricate it yourself.
In its testing of switches that had melted or actually caused a fire, Toyota says that nearly two-thirds of the cases showed evidence of such lubricants (which increase the risk of melting and fire).
Even so, Toyota says, short-circuits may also be caused by uneven application of the grease during the assembly of the switch.
The problem is rare. The 252 reports of window-switch problems, which ranged from a burning smell to an actual fire, represent only 7.8 cases per 100,000 affected vehicles, Toyota says. That's far less frequent than the 448 cases of inoperable switches per 100,000 vehicles.
When failures do happen, however, they can be troubling. In one case, a Toyota dealer found a dime-sized burn hole in the power-window master switch after a customer complained about smoke and a burning smell coming from the driver’s side-door panel. In another case, a driver claimed to have parked the car and was shopping when the driver's son called out that the door was on fire. The driver called the Boston Fire Department, which disconnected the battery.
Toyota has been aware of a potential fire hazard in its power-window master switches since at least 2009, when it recalled cars in China and Japan using substantially similar switches. At the time, the problem was thought to be too much grease, which was applied using different equipment and in a less-controlled way than it was for those vehicles destined for the US. That now looks like a flawed and potentially costly decision.
This year, Toyota sales have been rebounding smartly as its Japanese operations moved back to normal after last year's earthquake and nuclear disaster.
But the new recall risks reminding potential buyers of Toyota's recent sudden-acceleration problems, which tarnished its reputation for safety and triggered widespread recalls and investigations.
For more information on the Toyota recall, customers can call the company toll-free at 800-331-4331 or visit www.toyota.com/recall.