Owner's Manual
Page 271
... battery (1). Attach the other cable to the negative terminal of the booster vehicle and run it a few minutes. Start the engine of the booster battery (3). Discharged battery Jumper cables Booster battery 1. Remove the battery cover from the discharged battery (4). Mazda3_8V66-EA... in both vehicles to touch. If the booster battery is grounded. 3. Then start the engine of the other end to a solid, stationary, exposed metallic point (for example, the right hand side engine mounting bolt) away from its negative terminal is in another vehicle, don't allow both vehicles. ...
... battery (1). Attach the other cable to the negative terminal of the booster vehicle and run it a few minutes. Start the engine of the booster battery (3). Discharged battery Jumper cables Booster battery 1. Remove the battery cover from the discharged battery (4). Mazda3_8V66-EA... in both vehicles to touch. If the booster battery is grounded. 3. Then start the engine of the other end to a solid, stationary, exposed metallic point (for example, the right hand side engine mounting bolt) away from its negative terminal is in another vehicle, don't allow both vehicles. ...