Mobile battery replacement · Hybrid 12V auxiliary battery
Hybrid & EV 12V Battery Faults — Tile Hill
Tile Hill hybrid and EV 12V auxiliary battery support. We never touch high-voltage systems — the 12V side is where the fault almost always is.
It surprises people that an electric or hybrid car with a nearly full traction battery can be completely immobile. The high-voltage system cannot close its contactors without the little 12V battery, so a £120 part strands a car with a full charge.
Battery gone in Tile Hill? Rather than driving to a fitting bay and queuing, we come to the vehicle — driveway, workplace car park, or roadside on the M6 J2/J3 corridor.
Tile Hill covers a mix of buildings and driveways — post-war estates, modern infill — and we're set up to work in all of them, including tight residential streets.
Recent hybrid and EV jobs
Recent job nearby: a hybrid in Tile Hill completely unresponsive with a full traction battery. 12V auxiliary read 7.4V — replaced with an AGM unit, ready state confirmed on-site.
Recent job nearby: an EV near M6 J2/J3 that had been declared "needs recovery" by another provider. Powered up on the manufacturer jump points in under five minutes.
Working safely on the 12V side
- Only the 12V system is touched — the high-voltage traction system is never disturbed.
- Once powered, the vehicle's ready state is confirmed and DC-DC converter output is checked to be maintaining the 12V system.
- Fixed quoted price including battery, fitting, coding, recycling and warranty registration
- Every battery replacement finishes with a charging-system reading, so the same fault does not reappear next week.
Why a charged EV can be immobile
Home charging in CV4 does nothing for the 12V battery on many models, which is why owners are caught out despite a full charge.
Locally that means the streets between Tile Hill and Coventry, with access via M6 J2/J3 and M69 and a practical radius reaching Coventry (~4 mi) and Nuneaton (~9 mi).
Hybrid and EV questions
Q.Do you cover Tile Hill and the CV4 area for this?
Yes. Tile Hill is inside our routine coverage from Oldbury via M6 J2/J3, roughly 4 miles from Coventry. We cover it alongside Coventry 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.What do you do with my old battery?
It goes back to a licensed recycler. Around 99% of a lead-acid battery is recyclable. No landfill, and we don't charge for disposal.
Q.My EV has 80% charge — why is it dead?
Because the 12V battery powers the computers that close the high-voltage contactors. Without it, the traction battery cannot be connected to anything.
Q.Is it safe to jump a hybrid?
Yes, at the designated 12V jump points, which are what we use. The high-voltage system is not involved and should never be touched roadside.
Q.Does driving the car charge the 12V battery?
A DC-DC converter maintains it while the car is in ready mode. Short use and long standing still let it sink, exactly as with a conventional car.
Owners affected
Hybrid and EV owners across Tile Hill whose car will not go to "ready".
Domestically, post-war estates and modern infill dominate around here, which shapes how these jobs are accessed and worked.
Local reference data — Tile Hill
- Page focus
- Hybrid 12V auxiliary battery
- County
- West Midlands
- Typical property
- post-war estates and modern infill
- Main routes
- M6 J2/J3 · M69 · A45
- Postcode districts
- CV4
- Service covered here
- Battery Replacement
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
Working safely on the 12V side
Only the 12V system is touched — the high-voltage traction system is never disturbed.
- 4
Driveway fit
Memory saver in, old battery out, new one in and terminals torqued to spec.
Areas covered
Tile Hill sits about 4 miles from Coventry, and the same van covers Coventry (~4 mi), Nuneaton (~9 mi) and Bedworth (~5 mi) on the same run.
Full charge, still dead?
That is the 12V auxiliary. On-site testing and replacement across Tile Hill, without touching the high-voltage system. Tell us the vehicle and the symptom and you will get a firm price before anyone sets off.
Related pages
- Car Jumpstart — hybrid 12v auxiliary battery in Tile Hill
- Van Jumpstart — hybrid 12v auxiliary battery in Tile Hill
- Car won't start, no click — battery replacement in Tile Hill
- Taxi and private hire — battery replacement in Tile Hill
- Night and early hours — battery replacement in Tile Hill
- Hybrid 12V auxiliary battery in Coventry (~4 mi)
- Hybrid 12V auxiliary battery in Nuneaton (~9 mi)
- Hybrid 12V auxiliary battery in Bedworth (~5 mi)
- Hybrid 12V auxiliary battery across Coventry
- Battery Replacement in Tile Hill — main page
- All jumpstart services in Tile Hill
The short version
The 12V auxiliary is the weak link in hybrids and EVs. Test it, replace it with the right AGM unit, and the car comes back to life without recovery. If you would rather plan it than react to it, a battery replacement can be booked for a time that suits.
Stranded with a flat battery?
Call now or send a WhatsApp — we'll confirm your quote and dispatch the nearest engineer.