Battery Replacement

Typical Cost: Low (vehicles without stop/start) Medium (vehicles with stop/start)
Mobile Repair? Yes
Typical Lead Time: 2 - 24 hours

What does a car battery do?

The vehicle's battery is the power storage unit for starting its engine. It’s location, be it under the bonnet, under the seats or in the boot is vital to the vehicle's operation and without its successful recharging once the engine is running, will leave you unable to restart the engine after the next time it’s stopped.

These days, with more and more cars and vans being equipped with an automatic stop/start system to reduce emissions, having a battery that is in top condition is becoming even more important and also more expensive.

How does a car battery work and what are the components?

The majority of batteries used in cars and vans are 12v, which in essence means they comprise 6 cells with 2 plates per cell. One of the plates is made from lead and one from lead dioxide and are submerged in a sulphuric acid formula (known as electrolyte) which sets off a reaction on the lead dioxide plate and produces ions. These ions cause the lead plate to produce hydrogen and a lead sulphate.

The end result is a chemical reaction that produces electrons and these electrons generate electricity, which then comes out the positive terminal of the battery and flows round in a circuit back through the negative terminal. On the way round it can power a multitude of items, from the starter motor to the glove box light!

By applying a current to the battery in the right voltage, the battery can then be recharged.

In traditional wet flooded batteries and the newer enhanced flooded batteries (EFB) the electrolyte is in liquid form. In AGM batteries, the electrolyte is in gel form or in an advanced glass matt - hence AGM.

Typical symptoms that require a battery to be replaced.

You may initially find that when you unlock the vehicle, the central locking doesn’t work.
When you turn the key in the ignition, you have no lights on the dashboard.
When you attempt to start the engine, you get a very slow turn over, nothing at all or just a rapid clicking.

What happens during a battery replacement?

Changing a battery is a routine repair for all mechanics and can be done both kerbside as well as in the workshop, providing it is safe to do so. Due to the disconnection of the old battery and the connection of the new one, your radio code may be lost. It is important that you have this to hand and give it to the mechanic should they need to input the code into the radio in order for it to work.
Whilst there are variations between manufacturers, the basics are pretty similar.

The mechanic will;

Inspect the electrical system.
Remove the old battery.
Clean the battery cable terminals and check that the cables have not corroded or been damaged.
Fit the new battery and secure it into position.
If required by the vehicle, the battery will be coded to the vehicles electrical system.
Mechanic tests the battery charging system to confirm it is working as it should be.
If required and available, enter the radio security code and confirm its operation.
Ensure that electric windows close and open as they should.

What does this repair cover?

Unless otherwise stated, the quote for your battery to be replaced will cover;

The cost of the battery
Coming to you
Fitting of the battery
Coding of the battery to the vehicle's electrical system (if required)
Entering the radio code if required and present
Ensuring the electric windows close and open as they should
Checking that that charging system is working appropriately
Disposal of the old parts (unless you request to keep them)
VAT (if applicable)
12 months parts and labour warranty

What to search for on the ClickMechanic site?

Battery replacement (vehicles without stop/start system)
Battery replacement (vehicles with stop/start system)

How much does it cost to have a battery replaced?

The cost of a battery replacement depends on your car and what parts your car's manufacturer recommends.

Find out what you could save by visiting ClickMechanic

https://www.clickmechanic.com/jobs/car-battery-replacement

FAQ’s

Can I supply my own parts?

No, we will not fit customer supplied parts unless they are a brand new item, purchased from a dealership with the receipt as proof of purchase. There is no flexibility over this due to insurance and warranty issues.

What happens if the mechanic finds that the battery doesn’t require changing and the problem is due to another issue?

In this scenario, the mechanic will provide a no obligation quote for the correct repair. Should you accept this, the mechanic can alter the booking accordingly. If you decide not to go ahead with the alternative repair, the mechanic can change the booking to a call out and diagnostic booking and charge according to the time spent with the vehicle and call out.

Associated repairs carried out by ClickMechanic.

Battery condition check
Battery warning light inspection
Battery cable replacement
Alternator replacement
Starter motor replacement