i dont think ive ever used my series 1 at night until this last week and have noticed a problem with the electrics. when i turn my lights on to full beam the battery light comes on but only dim. if i use the indicators it comes on brighter. but if i was to say use the heated rear window it dosent come on any brighter.also the car splutters when coming on boost and it only does this with the lights on. could this be lack of power to the fuel pump perhaps?. the battery is new and so is the alternator. just wondering where is the best place to start checking the elctrics or has any body else had a similar problem