12V battery replacement
OEM-spec 12V battery swap with module reset.
The 12V auxiliary battery is the #1 cause of an EV that won't start, even when the traction pack is full. It powers the contactors, BCM, and infotainment — drain it, and the car is bricked. We replace with a sealed AGM rated for EV duty cycles, register the new battery with the BMS where required, and verify charging current from the DC-DC converter.
What's included
- OEM-equivalent 12V battery
- Module reset post-install
- Terminal clean + dielectric grease
- Old battery responsible disposal
Why this matters
A flat 12V battery on an EV often leaves you stranded with no way to even unlock the doors. The wrong replacement (cheap flooded battery vs AGM/EFB) causes premature failure within 6 months.
How it works
- 1
Test existing battery (cranking amps, internal resistance).
- 2
Recommend specific replacement.
- 3
Replace with engine off + memory-saver to preserve infotainment presets.
- 4
Register new battery to BMS (Tata, MG, Hyundai, Kia).
- 5
Verify DC-DC charge current.
What to expect
Allow 45 minutes. We pre-stock common sizes. If yours is unusual we'll order same-day for next-day fit.
What we typically find
From hundreds of inspections — what makes the report.
- Old battery showing cranking amps 30%+ below spec
- Corrosion at terminals (cleaned, no extra charge)
- DC-DC converter charge rate low (escalates to investigation)
How to prepare
- Save any custom infotainment presets via the OEM app if you can
Equipment we use
- Hioki battery analyzer
- Branded AGM batteries (Exide, Amaron, Bosch)
Certifications
- 1-year replacement battery warranty
Transparent pricing breakdown
No hidden charges. This is exactly what makes up your bill.
Test + diagnosis | ₹200 |
AGM battery (45Ah typical) Higher for premium 4Ws | ₹4,500 |
Fitment + BMS registration | ₹299 |
| Total | ₹4,999 |
Listed price ₹2,499 may differ from sum of line items due to package pricing. Workshop confirms before invoicing.
What customers say
“Registered the new battery to the BMS — something the local shop forgot last time. Charging cycle is now correct.”
FAQs
How long?+
30 minutes.
Home visit?+
Yes.
Reset matters?+
Yes — without it some EVs throw battery-management codes.
Who needs this
EVs older than 3 years, or with intermittent power-up issues.
Related services
Ready to book 12v battery replacement?
Fixed price ₹2,499 — no surprises. Or describe a different problem and we'll match the right service.