PARIS – A profit warning recently delivered by Nissan Motor Co. Ltd. Chairman Carlos Ghosn not only had the effect of lower prices for shares of Renault SA, which owns 44% of Nissan, it also raises questions about Ghosn’s ability to manage two auto makers.

Ghosn predicts Nissan’s profits will fall for fiscal year 2007, ending March 31, from an earlier anticipated ¥523 billion-¥460 billion ($4.4 billion-$3.8 billion).

The Nissan profit warning caused an immediate 8% drop in the auto maker’s shares and 3.6% in Renault shares, although prices rebounded some in the following days.

Ghosn plans to announce Renault’s 2006 results on Thursday (Feb. 8).

L’Expansion, a French investment magazine and website, refers to “certain specialists in the automotive sector,” who believe Nissan’s malaise could be due to the fact Ghosn has been chairman of both companies since Louis Schweitzer retired from managing Renault in April 2005.

“The man is not gifted with the ability to be ubiquitous,” writes the L’Expansion. “In other words, he is naturally less available for the one company as for the other.”

Ghosn, himself, seems to have raised the idea the Renault-Nissan Alliance might go back to the earlier organization, with each company having its own top boss.

In his profit warning, he spoke of an “interrogation on the way we are organized.”

Investir.fr, a French website, interprets the remark as a tacit understanding that Ghosn does not exclude the idea of changing “the organization of the double command that confers upon Ghosn the chairmanship of both Renault and Nissan.”

If there is any change in organization, it seems more likely Ghosn will appoint a new chairman for Nissan, while he remains in charge of Renault, whose shareholding gives it control of the Japanese auto maker.

While Nissan’s anticipated profit margin still is higher than 7%, second only to Toyota’s 9% among volume auto makers, the profit warning marks the first time since Ghosn joined Nissan in 1999 that the auto maker has had to do an about-face on its targets.

Ghosn built his reputation on the transparency of Nissan goals and the company’s ability to meet them.