AGM and EFB Battery Fitments Explained

By David Sholicar

If you have a Start-Stop engine, you need a Start-Stop battery. These batteries have been developed specifically for Start-Stop engines and can quickly recover power lost as a result of starting the engine. On many modern cars, the battery isn’t where you think it might be; other than in the engine bay, the battery can be found in the boot, under the passenger seat or under flooring. It can take up to two hours to change the battery on some vehicles! Even if the battery is in the traditional area, it can take a long time to fit a replacement battery; the battery box may be under another part or tucked behind a difficult to remove piece of equipment.

Absorbed Glass Mat (AGM) and Enhanced Flooded Batteries (EFB) have increased cyclic ability compared with a conventional battery and require a specific testing and fitting procedure. AGM and EFB batteries are monitored by an Intelligent Battery Sensor (IBS) which communicates the battery’s voltage, starting capacity and charging needs to the alternator. When an AGM or EFB battery is replaced the IBS needs to be told a new battery has been fitted, this is called battery validation. If the new battery isn’t validated it could fail prematurely, the Start-Stop function could be affected, and dashboard warning lights could come on.

It's important to note that if you have a Start-Stop AGM or EFB battery already fitted in your car, you must replace it like for like. Using a conventional battery in place of an AGM or EFB battery could cause serious and costly issues.

All our technicians are trained to test and fit all batteries, including Start-Stop AGM and EFB batteries.

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All batteries can be purchased at your local Protyre. With same day fitting available.

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About the author

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By David Sholicar
David is the National Retail Operations Manager for Protyre. One of David’s areas of responsibility and expertise is dealing with the DVSA and MOT’s for Protyre. As the Authorised Examiner Designate Manager ( AEDM ) David deals with applications for changes to the many Vehicle Testing Stations ( VTS’s) including managing the growth of the Number of MOT testing stations that Protyre operate, allocating MOT tester roles, and monitoring the MOT Test logs to ensure that Protyre MOT standards are maintained as the best in the industry.
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