Kia Optima: Change to "winter weight" oil if necessary

Check battery and cables

Winter puts additional burdens on the battery system. Visually inspect the battery and cables as described in section 7. The level of charge in your battery can be checked by an authorized Kia ...

Check spark plugs and ignition system

Inspect your spark plugs as described in section 7 and replace them if necessary. Also check all ignition wiring and components to be sure they are not cracked, worn or damaged in any way. ...

See also:

Inspection
Test the horn by connecting battery voltage to the 1 terminal and ground the 2 terminal. The horn should make a sound. If the horn fails to make a sound, replace it. Horn Relay Inspection 1. ...

Air cleaner
Filter replacement It must be replaced when necessary, and should not be washed. You can clean the filter when inspecting the air cleaner element. Clean the filter by using compressed air. ...

Antenna. Repair procedures
Inspection Glass Antenna Test 1. Wrap aluminum foil (A) around the tip of the tester probe (B) as shown. 2. Touch one tester probe to the glass antenna termin ...