SAN FERNANDO, Calif. (AP) _ Actor Todd Bridges of the ABC-TV show ''Diff'rent Strokes'' pleaded innocent Tuesday to three felony counts charging him with detonating a bomb in the car of an automobile customizer.

During a brief appearance before Los Angeles County Municipal Court Commissioner Charles Peven, Bridges pleaded innocent to exploding a destructive device, possessing a destructive device and possessing materials to manufacture a destructive device.

Deputy District Attorney Michael Knight said Bridges was ordered back to court for a May 21 preliminary hearing. Bail remained at the $10,000 already posted, he said.

Bridges, 20, allegedly exploded a plastic bomb in a Mercedes-Benz owned by Gregg Tyree on March 26. Knight said the explosion caused only minor damage and there were no injuries.

Bridges was upset with Tyree, who had been hired to customize the actor's Porsche sports car, because of the cost of the work and the length of time the car was in the shop, Knight said.

The actor was arrested in 1983 by Beverly Hills police after a loaded automatic pistol was found in his Porsche. Bridges claimed he needed the gun for protection. He was fined $240 after pleading guilty to carrying a concealed weapon.