Honda Civic Service Manual: Primary

Restraints

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Front Seat Belt Removal and Installation - Driver's Seat (2-door)

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

See also:

Honda Civic Owners Manual. Low Smart Entry Remote Signal Strength
The vehicle transmits radio waves to locate the smart entry remote when locking/ unlocking the doors and fuel fill door, opening the trunk, or starting the engine. In the following cases, locking/unlocking the doors, opening the trunk, or starting the engine may be inhibited or operation ...