Honda Civic Service Manual: Battery System

Electrical

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Battery Removal and Installation

Removal 1. Battery Terminal - Disconnection 1. Make sure the ignition switch is in LOCK (0). ...

See also:

Honda Civic Owners Manual. Automatic Power Off
If you leave the vehicle for 30 to 60 minutes with the shift lever in P*1 and the power mode in ACCESSORY, the vehicle automatically goes into the mode similar to VEHICLE OFF (LOCK) to avoid draining the battery. When in this mode: Except U.S. continuously variable transmission models The s ...