According to the old WSM... Frequency is set at 120Hz for a new alternator belt on the F355. When checked subsequently, it must not exceed 115~120. No lower limit is mentioned. Not sure why he still had power on the alternator after using the battery cutout switch, but it would have been easier to disconnect the battery terminals in the engine bay (right hand side) than to pull the wheel and wheel well liners off to get to the battery.
