Locate the battery - it is in the boot
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 the spanner on the bodywork!
Check the battery is generally secure, tighten the retaining clamp as required
To tighten, a 13mm socket is needed. Not too tight as you may damage the battery casing