I recently replaced the left bank valve cover gasket and seals due to oil leaking into the coil well. During the work I turned the ignition on to move the car. This acitivated the DCS and CATS fault lights because they were disconnected. After completing the work I can not reset the fault code warning lights. I disconnected the battery for a couple of minutes which didn't reset the lights (the radio stations weren't reset either). Do I need to disconnect the battery for a longer period?