"Nissan has newly found several non-conformities that may have caused inaccurate pass/fail judgements," the carmaker said in a press release.
The latest "non-conformities" involved inspections of brakes, steer wheels, speed measurements and vehicle stability, the company said.
Nissan has already revealed several other cases of improper inspections over the past year. The automaker had said in July that sample testing for emissions and fuel economy in final inspections at most of its factories in Japan did not meet domestic standards.
Since October last year, Nissan has recalled more than 1 million vehicles in Japan because of improper inspections.
(Reporting by Tim Kelly, Editing by Sherry Jacob-Phillips)