The US highway safety regulator does not expect Japanese firm Takata to be able to fully supply replacement parts for millions of defective air bags until January or later.
The National Highway Traffic Safety Administration, under pressure for its handling of the defective air bags connected to four deaths in Honda cars, has advised Takata and ten automakers to procure parts from other manufacturers.
It also asked other automobile manufacturers to be ready to expand their recalls beyond the hot and humid countries, such as Florida and Puerto Rico, which have been affected by the fault. The humidity in these regions reportedly may be affecting the propellant that is triggering the airbags in the event of a collision.
NHTSA Wants Answers
NHTSA deputy director David Friedman wants Takata to boost production and even source parts from competitors to meet demand.
Automakers must step up advertising to warn drivers of air bag dangers and offer loaner cars during repair. They could even test the Takata air bags themselves, Friedman wrote in a letter to manufacturers.
In a separate letter, to Takata Senior Vice President Kazuo Higuchi, Friedman demanded the Japanese firm provide updated estimates of its ability to manufacture replacement parts and asked for details about a programme to test inflators "as soon as possible".
US lawmakers have called for an independent evaluation of the NHTSA, to determine whether the agency could have done more to detect design hazards.
The agency briefed lawmakers earlier in the week.
The defective air bags, which can launch metal fragments into car occupants, have been linked to at least four deaths, all in Honda cars, and several serious injuries.
They have triggered the recall of over 10 million vehicles by 10 different car makers since 2008.