The alternator is key in keeping a constant charge to the battery on your Peugeot 107, which sends power to your starter motor, lighting and all other electrics on the vehicle. Once the engine is started a belt will turn the pulley on the alternator generating power which will be transfered to the battery, keeping it charged up. When your alternator develops an electrical fault it may stop charging the battery. If your car doesn't start you will need to check that the drive belt is still in place before diagnosing as a faulty alternator. If you need a new alternator then you are in the right place, orangespanner keep large stocks at fantastic prices from the best brands, all for fast delivery to your door.