i have the same fault ,the flame safety device is at fault,it detects heat from burner and should open gas supply ,when it fails the gas valve assumes flame is out ,so shuts down burner supply ,it consists of a capillary tube in copper attached to a brass node .which is attached to the thermostatic valve,(the brass node is located next to the main oven burner and should be end into flame)....so replace it.
steviewonder, April 2008