Once the switch is thrown, there should be no power in the engine bay. However, there is no safe way to test for power in the engine bay, since a simple slip of the wrench while removing the cables at the IMA motor could lead to arcing and burns or electrocution. The Honda manual states that the rear cover should be removed after the switch is thrown, and power should be checked at the battery pack using lineman’s gloves. Remember that your volt meter and leads should be in good condition, and rated to at least 500V. Otherwise it could still give you a shock. It’s a good idea to be very aware of what all of your body parts are touching while you are checking for power.