**Toyota chiefs are to begin testifying on safety issues later when the first of a series of US hearings begins.**The Japanese carmaker has recalled 8.5 million vehicles worldwide over safety concerns, the majority in the US.
James Lentz, head of Toyota in the US, will appear before the House Energy and Commerce Committee in Washington at 1100 local time (1600 GMT).
Toyota president Akio Toyoda is due to face the House Oversight and Government Reform Committee on Wednesday.
Robust sales
Toyota said on Tuesday that its global sales were 15% higher in January - when many of the recalls had already been announced - than they were a year ago.
Domestic sales jumped 45%, while overseas sales rose nearly 9%.
The company has been hit by three main safety problems - faulty accelerator pedals, accelerator pedals getting stuck in floor mats, and a problem with braking systems on its hybrid models.
On Monday, Toyota said it had received subpoenas asking it to produce documents relating to the safety problems and the company’s disclosure policies.