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Q: Alternator belt or whole new alternator?

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today the battery warning light came on (and stayed on throughout a 15min journey) in my 2010 Vauxhall Combo Van 1.7cdti.Battery was tested right away at Kwikfit and all ok.The warning light has gone off now and has stayed off but Kwikfit said that the alternator belt looks worn. They suggest i get a whole new alternator (total cost £434!!!). Can an alternator belt be replaced without having to replace the entire alternator? They said they would need to do diagnostics to confirm the alternator is the problem but had no one available to do that til next week. Suggested i just replace it all! no lights dimming in the car, radio works, headlights not dimming. Starts ok. No stalling. No noises. No smells. Kwikfit said the battery was being very slightly over charged so if i don't replace the alternator the battery will burn out. My question really is, because it's not confirmed as the actual alternator, could i not just ask for the belt to be replaced?

Hi There, If the diagnosis was that the battery is being overcharged, you may have a faulty voltage regulator that could be allowing the alternator to supply too much amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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