Mobile battery replacement · Alternator or battery?
Is It The Battery Or The Charging System? Harborne battery replacement
Not sure if it is the battery or the alternator in Harborne? We test both under load before recommending anything. Mobile battery replacement across B17.
A simple rule of thumb: a battery fault stops you starting, a charging fault stops you continuing. If the car jumps easily then dies a few miles later, the alternator is the prime suspect.
If your battery in Harborne is more than 4 years old and keeps going flat, you're past jumpstart territory — you need a proper replacement, fitted and coded on your driveway.
Harborne covers a mix of buildings and driveways — Edwardian villas, modern apartments — and we're set up to work in all of them, including tight residential streets.
How the two faults present
Around Harborne this comes up most with higher-mileage vehicles and with cars that have been repeatedly jumped by well-meaning neighbours.
Locally that means the streets between Harborne and Birmingham, with access via M6 J6 (Spaghetti Junction) and A38(M) Aston Expressway and a practical radius reaching Birmingham (~3 mi) and Smethwick (~3 mi).
Charging faults found nearby
Recent job nearby: a vehicle in Harborne jumped four times in a week. Charging voltage 12.7V at 2,000rpm with lights on — alternator, not battery, and the owner stopped throwing money at parts.
Recent job nearby: a car near Birmingham with an intermittent battery light. Ripple test showed a failed diode; the battery itself tested perfectly.
Jumped and died again?
That is a charging symptom. We test the alternator under real electrical load before anyone mentions a new battery. Same fixed pricing whether it is a battery replacement at 9am or 3am, anywhere in Birmingham City Council.
The readings that separate them
- Engine-running voltage should sit roughly between 13.8V and 14.7V — below 13.2V under load is a charging fault regardless of how new the battery is.
- Engine-off resting voltage establishes the battery's state of charge before anything else is judged.
- Old battery taken away for proper lead-acid recycling — no charge, no landfill, DVSA-compliant paperwork
- Every battery replacement finishes with a charging-system reading, so the same fault does not reappear next week.
How the visit runs
- 1
Vehicle lookup
By reg on the phone — we confirm the exact OEM battery spec before quoting.
- 2
Fixed all-in price
Battery, fitting, coding, recycling, warranty — one number on the phone.
- 3
Driveway fit
Memory saver in, old battery out, new one in and terminals torqued to spec.
- 4
Register + verify
OBD coding done, warranty registered, alternator output checked before we leave.
Local reference data — Harborne
- Service covered here
- Battery Replacement
- Local authority
- Birmingham City Council
- County
- West Midlands
- Reference point
- Queen Elizabeth Hospital
- Page focus
- Alternator or battery?
- Typical property
- Edwardian villas and modern apartments
Areas we test in
Harborne sits about 3 miles from Birmingham, and the same van covers Birmingham (~3 mi), Smethwick (~3 mi) and Sutton Coldfield (~7 mi) on the same run.
Alternator vs battery questions
Q.Do you cover Harborne and the B17 area for this?
Yes. Harborne is inside our routine coverage from Oldbury via M6 J6 (Spaghetti Junction), roughly 3 miles from Birmingham. We cover it alongside Birmingham and the surrounding streets.
Q.How do I know my battery needs replacing rather than jumpstarting?
If it's over 4 years old and going flat repeatedly, or the CCA on a load tester reads under 60% of rated, it's replacement time. Jumpstarting will only get you a day or two.
Q.Do I really need OBD coding when the new battery goes in?
On post-2012 BMW, Audi, VW, Ford, Vauxhall, Peugeot and Citroen — yes. Without coding, the alternator will overcharge the new battery and kill it in under a year.
Q.The car started on jump leads and then died. What does that mean?
Classic charging fault. The engine ran on borrowed energy and stopped when the battery could no longer supply the ignition system.
Q.Can a bad alternator ruin a new battery?
Yes, in both directions. Undercharging sulphates the plates; overcharging boils off electrolyte. Both shorten life dramatically.
Q.Do you replace alternators too?
We diagnose them on-site and can replace batteries on the spot. Alternator replacement is a workshop job, and we will tell you exactly what needs doing so you are not paying for diagnosis twice.
Why this is safe to book
- Where the fault is beyond our scope we say so plainly instead of selling a battery anyway.
- Fixed prices agreed before dispatch — no callout fee just to open the bonnet in B17.
Related pages
- 24/7 Emergency Jumpstart — alternator or battery? in Harborne
- Car Jumpstart — alternator or battery? in Harborne
- Keyless entry and immobiliser issues — battery replacement in Harborne
- Roadside emergency — battery replacement in Harborne
- Jump leads didn't work — battery replacement in Harborne
- Alternator or battery? in Birmingham (~3 mi)
- Alternator or battery? in Smethwick (~3 mi)
- Alternator or battery? in Sutton Coldfield (~7 mi)
- Alternator or battery? across Birmingham
- Battery Replacement in Harborne — main page
- All jumpstart services in Harborne
The short version
Storage fault or supply fault — the tests are different, the costs are different, and guessing is expensive. Every visit here includes the charging check. Locally this is handled alongside Birmingham and Smethwick, so the van is rarely far away.
Stranded with a flat battery?
Call now or send a WhatsApp — we'll confirm your quote and dispatch the nearest engineer.