COMPRESSOR 4511179 - Caterpillar

The battery cables or the batteries should not be removed with the battery cover in place. The battery cover should be removed before any servicing is attempted.Removing the battery cables or the batteries with the cover in place may cause a battery explosion resulting in personal injury.
Turn the start switch to the OFF position. Turn the ignition switch (if equipped) to the OFF position and remove the key and all electrical loads.
Disconnect the negative battery terminal at the battery that goes to the start switch. Ensure that the cable cannot contact the terminal. When four 12 V batteries are involved, the negative side of two batteries must be disconnected.
Tape the leads in order to help prevent accidental starting.
Proceed with necessary system repairs. Reverse the steps in order to reconnect all of the cables.