When Disconnecting and Connecting a 12 Volt Car Battery

Disconnecting

When disconnecting a 12 volt automotive battery, remove the negative terminal first.  Removing the ground terminal first, minimizes the possibility of shorting the positive terminal to metallic tools and under hood components.

Connecting

 When connecting a battery, connect the positive cable first.  This helps to prevent damaging voltage spikes from back feeding through your electrical system.

 

In conclusion:  Remove the ground cable first when removing a battery.  Attach the ground cable last when installing a battery. 

 

Warning - always wear personal protective equipment when handling automotive batteries

Always wear approved shielding to protect eyes, face and body when working near a battery. 

Never expose a battery to flames or sparks.  Batteries (especially when charging ) can form explosive hydrogen gas.  Any ignition source could trigger a violent battery explosion.

Remove all jewelry before working around batteries.  Jewelry worn on the hands can easily short between the positive battery terminal and metallic tools.

Note:  This is not a comprehensive list of battery handling precautions.  Consult with your vehicle and battery owners manual for additional safety guidelines.