Description And Operation: Description

1. The CMF (Closed Maintenance Free) battery is, as the name implies, totally maintenance free and has no removable battery cell caps.
2. The CMF (Closed Maintenance Free - Openable Type) battery does not require water replenishment for the maintenance, but there are the cell caps to be able to add distilled water if necessary.
3. The battery is completely sealed, except for small vent holes in the cover.

Courtesy of HYUNDAI MOTOR AMERICA

Information 

• After disconnecting then reconnecting the battery negative cable, reset some parts that require the reset procedures. (Refer to Body Electrical System - "GENERAL INFORMATION ")