Honda Civic Service Manual: Engine Cooling

Engine

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Coolant Replacement (R18A9)

1. Radiator Cap 1. Wait until the engine is cool, then carefully remove the radiator cap. ...

See also:

Honda Civic Owners Manual. Ignition Switch
Ignition Switch* Manual transmission models WARNING Removing the key from the ignition switch while driving locks the steering. This can cause you to lose control of the vehicle. Remove the key from the ignition switch only when parked. Continuously variable transmission models You ca ...