What is the primary reason to disconnect the battery before repairs?

• A. To prevent electrical shock or accidental deployment of airbags
• B. To improve radio reception
• C. To drain the battery quickly
• D. To reset the odometer

Answer: (A)

Safety comes first when working on a vehicle’s electrical system. Disconnecting the battery isolates power and greatly reduces the risk of electrical shock and accidental airbag deployment while you’re under the dash or near airbag modules, since these systems can deploy if circuits are disturbed during repairs. In practice, the negative terminal is disconnected first to minimize the chance of a short to ground, then reconnected after work is finished. The other ideas—improving radio reception, draining the battery, or resetting the odometer—aren’t the reasons for this safety step.