Volvo 2006 C70 - Manual (Page 144)

pg. 162 Maintenance and servicing
Battery
Battery maintenance
Driving habits and conditions, climate, the number of starts, etc., all affect the service life and function of the battery.
In order for your battery to perform satisfactorily, keep the following in mind:
Check the fluid level in each cell in the battery every 24 months or every 15,000
1
miles (24,000 km), whichever is
sooner. The fluid should be at the level shown in the illustration above (A). Do not overfill.
Use a screw driver to open the caps and a flashlight to inspect the level.
If necessary, add distilled water. The level should never be above the indicator (A).
The fluid level should be checked if the battery has been recharged.
After inspection, be sure the cap over each battery cell is securely in place.
Check that the battery cables are correctly connected and properly tightened.
Never disconnect the battery when the engine is running, or when the key is in the ignition. This could damage the
vehicle's electrical system.