* Kobe Steel CEO to resign in April, successor not named
* Company past littered with compliance failures, malfeasance
* Kobe Steel says pay of executive officers to be cut
* Company still under U.S. Justice probe, fines possible (Recasts with CEO resignation, details)
TOKYO, March 6 (Reuters) - Kobe Steel Ltd said on Tuesday its CEO will step down to take responsibility for a widespread data fraud scandal, although doubts remain over the company's corporate culture and possible fines.
Japan's third-largest steelmaker, which supplies steel parts to manufacturers of cars, planes and trains around the world, admitted last year to supplying products with falsified specifications to about 500 customers, throwing global supply chains into turmoil.
Hiroya Kawasaki will resign as CEO and Chairman on April 1, with his successor to be decided at a board meeting to be held soon, the company said.
"We discovered that inappropriate actions were widespread, and were carried out with the knowledge and involvement of many, including management," it said in a statement published along with results of a four-month probe by external investigators.
"Considering the multiple compliance issues that we've had in the past, we must say that there are deep-rooted problems, not only in terms of compliance but also in the corporate culture and mindset of employees and management."
Kobe Steel also announced the resignation of Executive Vice President Akira Kaneko and temporary pay cuts of up to 80 percent for all internal executive officers.
The case was one of the country's biggest industrial scandals in recent memory, which set off a rash of malfeasance revelations by other Japanese heavyweights, hitting the country's reputation for manufacturing excellence.
In the past several months, Mitsubishi Materials Corp , Toray Industries and Ube Industries have also admitted to product data fabrication while automakers Nissan Motor and Subaru Corp have revealed incorrect final inspection procedures.
Kobe Steel is currently undergoing a U.S. Justice Department probe, meaning it still faces legal and financial risk. It has also had a Japanese government-sanctioned seal of quality revoked on some of its products.
($1 = 106.1500 yen) ( Reporting by Yuka Obayashi; Additional reporting by Chris Thomas and Indranil Sarkar in BENGALURU, Minami Funakoshi in TOKYO; Writing by Ritsuko Ando; Editing by Stephen Coates and Tom Hogue)