Takata plant Mexico
The Mexican and the Japanese national flags are seen outside the Takata plant, the world's second-largest supplier of airbags and seat belts, in Monclova, in northern Coahuila state, April 11, 2013. The defective air bag infiltrators originated from this factory. Reuters/Daniel Becerril

Executives from Japanese auto safety parts manufacturer Takata Corp., as well as Honda and Chrysler, faced questions from U.S. senators on Thursday over the millions of potentially fatal, defective air bag systems that are linked to at least six deaths. The hearing began with a call on automakers to step up efforts to accommodate consumers while companies struggle to obtain parts to replace faulty systems.

Sen. Bill Nelson, D-Fla., said in his opening remarks that “because of people driving around with a defective air bag in the steering wheel and dashboard -- the automobile makers need to provide a loaner [vehicle]” while companies repair recalled cars.

The demand to provide loaner vehicles would require 10 automakers (see below for an updated list of affected cars) to make costly arrangements with dealerships to provide customers with temporary replacement cars as they deliver parts and make the necessary repairs. Under current U.S. regulatory law, car companies aren't compelled to make these accommodations even if the defect is potentially fatal. Earlier this year, General Motors voluntarily provided this service to owners of 2.59 million older sedans containing a defective ignition switch.

The news comes as the U.S. National Highway Traffic Safety Administration faces criticism for initially allowing region-based recalls of the affected cars. On Tuesday, NHTSA backtracked and expanded the recalls to all affected cars nationwide. Previously, NHTSA allowed Takata and automakers to limit the recall to areas of the country with high humidity, because according to Takata, the cause of the flaw is extended exposure to moist air that causes water contamination of the chemicals inside the air bag inflator.

Takata is struggling to make replacement parts fast enough. NHTSA told Bloomberg last month that Takata would have two production lines installed by January to speed up the production of replacement air bag systems.

Here’s the latest list of vehicles affected by the faulty Takata air bag systems:

Honda/Acura: 5,051,364 potentially affected vehicles
2001 – 2007 Honda Accord
2001 – 2005 Honda Civic
2002 – 2006 Honda CR-V
2003 – 2011 Honda Element
2002 – 2004 Honda Odyssey
2003 – 2007 Honda Pilot
2006 – Honda Ridgeline
2003 – 2006 Acura MDX
2002 – 2003 Acura TL/CL
2005 – Acura RL

Toyota/Lexus: 877,000 potentially affected vehicles
2002 – 2005 Lexus SC430
2002 – 2005 Toyota Corolla
2003 – 2005 Toyota Matrix
2002 – 2005 Toyota Sequoia
2003 – 2005 Toyota Tundra

Nissan/Infiniti: 717,364 potentially affected vehicles
2001 – 2003 Nissan Maxima
2001 – 2004 Nissan Pathfinder
2002 – 2006 Nissan Sentra
2001 – 2004 Infiniti I30/I35
2002 – 2003 Infiniti QX4
2003 – 2005 Infiniti FX35/FX45
2006 Infiniti M35/M45

BMW: 627,615 potentially affected vehicles
2000 – 2005 3 Series Sedan
2000 – 2006 3 Series Coupe
2000 – 2005 3 Series Sports Wagon
2000 – 2006 3 Series Convertible
2001 – 2006 M3 Coupe
2001 – 2006 M3 Convertible

Chrysler Group: 371,309 potentially affected vehicles
2003 – 2008 Dodge Ram 1500
2005 – 2008 Dodge Ram 2500
2006 – 2008 Dodge Ram 3500
2006 – 2008 Dodge Ram 4500
2008 – Dodge Ram 5500
2005 – 2008 Dodge Durango
2005 – 2008 Dodge Dakota
2005 – 2008 Chrysler 300
2007 – 2008 Chrysler Aspen

Mazda: 64,872 potentially affected vehicles
2003 – 2007 Mazda6
2006 – 2007 Mazdaspeed6
2004 – 2008 Mazda RX-8
2004 – 2005 MPV
2004 B-Series Truck

Ford: 58,669 potentially affected vehicles
2004 – Ranger
2005 – 2006 GT
2005 – 2007 Mustang

Subaru: 17,516 potentially affected vehicles
2003 – 2005 Baja
2003 – 2005 Legacy
2003 – 2005 Outback
2004 – 2005 Impreza

Mitsubishi: 11,985 potentially affected vehicles
2004 – 2005 Lancer
2006 – 2007 Raider

General Motors/Saab: undetermined number of potentially affected vehicles 2003 2005 – Pontiac Vibe
2005 – Saab 9-2X

Correction: The original story said Sen. Richard Blumenthal, D-Conn., called on automakers to provide loaners to owners of affected vehicles. It was Sen. Bill Nelson, D-Fla., who made the call.