Car checks expose an individual to several dangers, one of them is shock. An electric shock can be triggered by a key as soon as it touches a piece of metal, while disconnecting the main negative. By touching a positive electrical part, the wrench acts as an arc welder, so it is good to disconnect the main negative cable first. To ensure that no damage is caused to the batteries, it must be ensured that they recognize both negative and positive signs. The negative terminal is marked with a black wire and a – sign, while the positive terminal is marked with a red wire and a + sign. For safety reasons before disconnecting the terminals, it is a good idea to ensure that you understand the