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FLAT BATTERY

Run out of juice?

We'll get you going again in no time

We won’t just jump-start you and send you on your way; if we can't find the reason for the drained battery or we suspect that the battery may be faulty then we'll carry out a battery test. 

We test batteries very carefully and only recommend replacement if it’s really necessary.

Give us a call on 0800 88 77 66.

What do we do?

  • test your battery
  • check your car's charging system
  • check for a fault that could be draining your battery
  • partially charge your battery or replace it, if required, so you can continue your journey.

What’s involved?

Before we start your engine, we’ll use Conductance technology to measure the health of your battery. We can get the most accurate reading by testing when your battery is in a ‘rested state’.

Because the tester’s already pre-programmed with data, we can get an immediate printout of your battery’s readings compared with what they should be. 

The printout can tell us the condition of your battery. It may say:

  • 'A bad cell':  Car batteries contain several 2-volt batteries (known as cells). Unfortunately, if one is defective the battery will need to be replaced.
  • 'Replace battery': Very straightforward; it’s clear that the battery’s just not up to it anymore.
  • 'Needs charging': This means that your battery’s within spec but just needs a full recharge. We’ll check your charging system to try to get to the bottom of what’s drained it, and then give you a jump start. We’ll recommend you get a full recharge as soon as possible and advise how long the battery will need to be charged and by what method. The battery test gives an indication of the time required to fully recharge the battery using the vehicle charging system but in some cases a bench charge may be required..
  • 'Consider Replacement': Your car battery has passed the battery test but the result was a borderline pass indicating a battery nearing the end of its useful life. The patrol will give you advice on how soon you should consider changing the battery based on how you use your vehicle.
  • 'Good battery': There’s nothing wrong with your battery. It’s within spec and in good condition. Obviously it’s still dead, so we’ll check your car’s charging system and investigate what’s caused the breakdown.

To try and avoid flat batteries in the future, here’s our quick guide to keeping them running. 

Flat battery

Why do batteries go flat?

There are all sorts of reasons, but the most common are:

  • a car being left unused for a while, or only used for short journeys
  • a light being left on
  • a faulty component
  • a problem with the car’s charging system
  • a fault with the battery itself

Batteries can fail for other reasons too. Excessive vibration, over-charging, corrosion and extreme heat or extreme cold.

What makes them last longer?

The reason why batteries fail if they’re not used, or they’re only used for stop-start or short journeys, is that they don’t get the chance to recharge properly. 

The technical explanation is that this 'under charging' leads to 'sulphation' if the battery voltage is allowed to remain below 12.4 volts. Sulphation is the hardening of the lead plates within the battery and it reduces the battery's ability to accept or hold a charge.

If you do only use your car occasionally and for short journeys it's worth investing in an intelligent charger/battery conditioner. This can be left connected for long periods without risk of damage to the battery.

Alternatively, you could get a solar charger - it won't charge a battery from flat but will help to keep the battery charged on a vehicle that you don't use much or only use for short journeys.


Updated 23 July 2018

Don’t use your car much?

A charger will help to keep your car battery working – take a look at our products on Amazon.