How Much Does An Alternator Replacement Cost in the UK?

An alternator creates an alternating current (AC) which is then rectified to DC to power the vehicle's electrical system and recharge the battery. If your car's alternator is starting to fail, you'll likely see some warning signs. These can include the battery warning light coming on, dimmer headlights, problems starting your car and strange noises coming from under the bonnet. If you notice any of these issues, it is likely that you will need an alternator replacement. It’s important to get a failing alternator checked and replaced as it could eventually lead to the battery running flat and engine stalling.

How much does it cost to replace an alternator?

The average cost of replacing an alternator is £250, with prices ranging from £150 to £400. The exact price of an alternator replacement depends largely on your car and the parts your car's manufacturer recommends.

Your location can also be a key factor in determining the price of an alternator replacement. For example, average hourly labour rates and demand in cities like London is around £50-£100 while in towns with lower demand, the labour rates can range from £35-£50. The type of mechanic, for example, a mobile mechanic vs a dealership garage technician can also affect the total cost of an alternator replacement.

Average cost of an alternator replacement by location

To avoid having car owners overpaying and get a fair price for an alternator replacement, we use real-time data of thousands of car makes and models data, local labour prices for alternator repairs and replacements and alternator part prices to provide an instant fair quote. Simply enter your vehicle registration number and postcode to get an instant price for an alternator repair or replacement for your car.

Average cost of an alternator replacement by manufacturer

Signs your alternator needs to be replaced

If your car's battery is not being charged, it could be a sign that your alternator needs to be replaced. Look out for the tell-tale signs of a failing alternator:

• Trouble starting the car
• Electrics malfunctioning
• Battery warning light
• Dead battery
• Dim or flickering lights
• Engine running rough or stalling
• Burning smell from under the bonnet
• Issues with accessories such as power mirrors

A "check engine" light or warning light may come on

Due to the lack of sufficient power supplied, the engine management light or the battery warning light may illuminate indicating a problem that needs attention.

Trouble starting the car

The battery provides power to start the vehicle but the alternator charges the battery when the vehicle is running. If the battery can’t be charged due to a faulty alternator, then the car won’t start.

Dim or flickering headlights

The alternator is responsible for supplying power to the vehicle's electrical system, and if it is not working properly, the headlights will start to flicker or be dimmer than usual.

Electrics malfunctioning

The electricity created by the alternator is also what powers the vehicle’s electrics such as the power windows, radio system, power mirrors, headlights, entertainment, etc. A failing alternator
is likely to cause one or more of these components to malfunction.

Frequently asked questions about alternator replacement

What does replacing an alternator involve?

Depending on the make and model of a vehicle, the location of an alternator and the parts needed will determine the process followed in an alternator replacement job. However, the following steps are more or less what is followed by a qualified mechanic booked via ClickMechanic:

• Mechanic will inspect the car's battery charging system.
• Mechanic will inspect the alternator's ancillaries (drive belt, cables etc.)
• Mechanic will test the voltage output of the alternator.
• If necessary, the mechanic will replace the alternator.
• Mechanic will advise if any other parts of the electric system need to be replaced.
• Mechanic will test the charging system and will test drive the car.
• You may attempt to change an alternator yourself with this guide. However, beware that this is a job best left to qualified mechanics as it involves work with electrical components of the vehicle which can be dangerous if done without the proper skills and tools.

How to extend the life of an alternator?

There is no surefire way to extend the life of an alternator, but preventative maintenance is always the best approach. Getting your battery condition checked and tested as well as proper care and regular servicing will help to ensure that the alternator lasts as long as possible.

How long does an alternator replacement take?

Replacing an alternator can take anywhere from 1 to 2 hours depending on the make and model of the vehicle.

Can an alternator be repaired?

Yes, an alternator can be repaired but it’s usually a specialist job and can take hours to fix. It’s almost always more cost-effective to get an alternative replaced rather than attempt to repair it.

Can I carry out an alternator replacement myself?

An alternator replacement job involves work with electrical components which involves a safety risk. If you’re not familiar with electricals and are not a qualified mechanic, we recommend seeking professional help to change a faulty alternator.
ClickMechanic can help get you a vetted and local mechanic to carry out the work. Just enter your postcode and your car's registration number at the top of this page and select the work needed to get an instant fixed price up front.

What else could be the problem if my car alternator isn’t broken?

• Battery issues - if you’re experiencing issues such as trouble starting the car or electrics malfunctioning it could be the battery that is weak. In this case, you’ll need to get the battery voltage checked and replaced as needed.
  
• Wiring - in some cases, the wires connecting the alternator to the electrical components can become damaged or corroded over time and will need to be replaced.
• Engine oil leak - a burning smell from under the bonnet could also be a sign of a engine oil leaking and coming in contact with a hot vehicle part
• Alternator drive belt - If the belt is worn or not correctly tensioned this can affect alternator's performance