The information, which would include repair manuals and spare part catalogues, would make it easier for consumers and independent repair shops to fix cars, analysts said, putting pressure on official car dealerships to cut prices on repairs and parts at a time when sales of new cars have come to a standstill.

"This is a countermeasure to try to make original dealership prices more affordable to the consumers," said Yale Zhang, Shanghai-based managing director at Automotive Foresight.

Such detailed information would make it easier for third-party repair shops to identify suppliers and source parts directly, Zhang added.

The new policy, announced in a joint statement from eight government ministries and departments, is the latest in a series of measures China has taken to crack down on price fixing in spare parts and repairs after fining several automakers since 2014 including Daimler AG (>> Daimler AG) and Nissan Motor (>> Nissan Motor Co Ltd).

The monopoly crackdown is one of the key factors putting pressure on profits from repairs, at a time when companies like BMW AG (>> Bayerische Motoren Werke AG) are looking to after-sales to supplement slumping profits from new cars.

Prices of spare parts and repairs in China can often be several times more expensive than other markets.

Auto sales in China were flat in the first eight months of the year and could drop this year for the first time since the market took off in the late 1990s.

Average per customer revenue from after-sales services dipped to 3,480 yuan ($546) this year from 4,288 yuan last year for luxury car brands and to 1,558 yuan from 1,710 yuan for the mass market segment, according to a study by J.D. Power & Associates released in July.

(Reporting by Jake Spring; Editing by Miral Fahmy)

Stocks treated in this article : Bayerische Motoren Werke AG, Daimler AG, Nissan Motor Co Ltd