By David Morgan

WASHINGTON (Reuters) -- Two months after receiving a record $105 million fine for lapses in U.S. auto safety recalls, Fiat Chrysler Automobiles NV faces new problems over lax safety reports that could lead to additional financial penalties for the Italian-U.S. automaker.

Federal regulators said on Tuesday they uncovered an apparent discrepancy at Fiat Chrysler in Early Warning Report data that automakers must provide to the National Highway Traffic Safety Administration under federal law. A subsequent in-house investigation by the company found that information including auto-related death and injury claims had gone under-reported.

"This represents a significant failure to meet a manufacturer’s safety responsibilities," NHTSA Administrator Mark Rosekind said in a statement.

Early Warning Reports provide data that could identify safety defects and ultimately lead to recalls. Neither Fiat Chrysler nor NHTSA identified the vehicles involved and it was not clear whether the under-reporting would have triggered a recall if identified earlier.

The automaker said it was in regular communication with NHTSA about its internal investigation and "takes this issue extremely seriously, and will continue to cooperate with NHTSA to resolve this matter and ensure these issues do not re-occur."

NHTSA first discovered the safety reporting discrepancy in late July, around the same time that regulators and Fiat Chrysler announced an agreement intended to end years of contention over lapses in the automaker's performance on safety recalls covering millions of vehicles.

The deal required Fiat Chrysler to make a $70 million cash payment, spend $20 million to improve its recall process and pay an additional $15 million if the automaker committed further violations.

Fiat Chrysler could be required to pay the deferred $15 million sum if regulators find that the early warning report problem amounts to a new violation of federal law, NHTSA said.

In January, regulators announced $70 million in fines against Honda Motor Co Ltd over the carmaker's failure to report deaths, injuries and other information in Early Warning Reports to the federal government.

NHTSA said the new Fiat Chrysler probe is still in its early stages.

"Preliminary information suggests that this under-reporting is the result of a number of problems" with Fiat Chrysler’s early warning report systems, Rosekind said.

"NHTSA will take appropriate action after gathering additional information on the scope and causes of this failure,” he added.

(Reporting by David Morgan; editing by David Gregorio and Christian Plumb)