WASHINGTON - The National Highway Traffic Safety Administration is looking into complaints from owners of 2000-'01 who say the hoods of their vehicles have opened unexpectedly while driving. The federal government says an estimated 697,480 Dodge Rams are involved in the investigation, which began in late July.

NHTSA says there have been no reports of injuries or fatalities connected with the investigation. However, it has received 30 complaints from owners of the Dodge Ram that hoods had opened while driving, 'blocking their visibility and in some cases smashing into and damaging their windshield and/or roof.'

'The secondary hood latch may bind and not secure the hood,' according to NHTSA's defect investigations summary. 'Many of the complaints specify that the secondary hood latch components were corroded.

'The corrosion appears to prevent the latch from operating properly.'

The federal government warns owners of the affected trucks that the 'malfunction would not be obvious to the driver.'

'The hood could open unexpectedly while the vehicle is underway,' said NHTSA. 'Sudden and unexpected opening of the hood startles drivers, blocks their visibility, and could lead to a crash into other vehicles or objects.'

A defect investigation is sometimes a precursor to a recall of the vehicle.