Service · Stop-start system
Start-Stop Battery Replacement Service
Start-stop battery replacement on your driveway: the correct AGM or EFB battery, BMS coding and the old battery recycled, West Midlands wide. 07886 626640.
Every stop-start car needs a specific battery type, AGM or EFB depending on the manufacturer, and a specific coding step to register the new battery to the vehicle's Battery Management System.
Skip either and stop-start will refuse to engage, or the new battery will fail early. We do both correctly on the driveway.
Who calls us for this
Drivers of any petrol or diesel from ~2012 onwards where stop-start has stopped working.
What we actually see on these jobs
- Fitting a standard flooded battery instead of AGM/EFB is the top cause of repeat failure we see.
- BMS coding is not optional, the alternator field voltage stays wrong until it's done.
- Stop-start re-engagement is verified as part of every fit before we take payment.
Standard vs start-stop battery
A start-stop battery is built to restart the engine many times on every journey and to power the car while the engine is off at the lights. A standard flooded battery is not designed for that cycling and wears out quickly when fitted to a start-stop car. Start-stop batteries come in two types, EFB for less demanding systems and AGM for more demanding ones, and the car is designed around one or the other.
Does start-stop use the battery? Yes, much more than a conventional car does. Each stop runs the electrics from the battery, and each restart draws a heavy current. The car's battery management watches the battery's condition and stops using start-stop when charge is low, which is why a weak battery is often the first sign that start-stop has stopped working.
How much are start-stop batteries?
Start-stop batteries cost more than standard batteries because of their construction, and the price depends on whether the car needs EFB or AGM, the case size and the rating. Larger models, such as a Volvo XC90, can need a different battery from smaller cars, so start-stop battery cost in the UK is best answered from the registration. Coding the new battery to the car is part of the fitted quote where the manufacturer requires it.
Key facts, Start-stop battery service
- System
- Stop-start / auto-start-stop / ISG
- Battery types
- AGM (premium) or EFB (entry level)
- Coding
- OBD-level BMS registration, mandatory
- Verification
- We check stop-start re-engages before leaving
Start-stop battery service, specific questions
Q.How do I know if my car has AGM or EFB?
The battery label says. If it's already gone, we look up the correct spec by reg, we won't guess.
Q.Will stop-start work immediately after replacement?
Usually within a short drive as the BMS re-learns. It should re-engage the same day.
Q.Do I need to go to a dealer for the coding?
No, we do OBD-level coding for BMW, Audi, VW, Mercedes, Ford, Vauxhall, PSA on the driveway.
Q.What is the difference between a standard and a start-stop battery?
A start-stop battery, EFB or AGM, is built for frequent restarts and powering the car with the engine off. A standard flooded battery is not, and wears out quickly in a start-stop car.
Q.Why has start-stop stopped working on my car?
Often because the battery is weak. The car disables start-stop when charge is low to protect starting. A test shows whether the battery needs replacing or the system needs looking at.
Our four-step process
- 1
Fixed quote
By postcode and reg, before we move.
- 2
Load test
So we're not selling you a battery you don't need.
- 3
Correct spec
AGM, EFB or standard flooded, matched to your car, not what's cheapest.
- 4
Coded & clean
BMS registered, terminals greased, old unit recycled.
Related guides
General questions
Q.What warranty comes with a new battery?
Tier-1 batteries with 2 to 4 year warranty depending on chemistry (standard flooded, EFB or AGM). Warranty is transferable and registered on the day.
Q.Are you insured?
Yes, fully insured with public liability and goods-in-transit on every callout and every battery we fit.
Q.What payment methods do you accept?
Card, contactless, Apple Pay and Google Pay on the driveway. Bank transfer accepted for accounts. No cash-only surprises.
In short
Stop-start systems need exact-spec batteries plus coding. That's the whole job, and that's what we do.
Stop-start failing? Correct battery, coded, verified working.
AGM or EFB per spec, BMS coding, stop-start reset, one visit.
Stranded with a flat battery?
Call now or send a WhatsApp, we'll confirm your quote and dispatch the nearest engineer.