Locate the battery - it is set into the floor
First, lift up the carpet
Check the Negative (-) terminal clamp is tight
Open the 'Positive' (+) protective cover
Check the Positive (+) terminal clamp is tight. CAUTION If using a spanner to tighten terminal, be careful not to short it on the bodywork
Check battery is generally secure, if loose, tighten the battery retainer
Tighten if required, a 10mm socket or spanner is needed. Not too tight because you may damage the battery casing. Replace carpet