Which Tesla battery has gone?
A Tesla has two batteries. The high-voltage pack under the floor drives the car. A much smaller low-voltage battery runs the locks, screens and computers, the job a 12-volt battery does in a petrol car.
The small one wearing out is routine maintenance. The big pack is a different job altogether, so work out which one the message on your screen means before you go further. A photo of it helps the mechanic.
What the Tesla battery warranty says
CarsGuide's January 2026 report puts the Model 3 RWD and Model Y RWD at eight years or 160,000 km, and every other Model 3 and Model Y at eight years or 192,000 km. The same cover applies to the drive unit (the motor and gearbox assembly that turns the wheels).
Both terms come with at least 70 per cent of battery capacity over that period. So some lost range is normal, and on its own it isn't a claim. A pack that's dropped below that line inside the term is worth putting to Tesla in writing.
For a Model S or Model X, read the warranty document for that car.
The rest of the warranty changed in 2026
New Model 3 and Model Y cars delivered from 1 January 2026 get five years with unlimited kilometres, or five years or 150,000 km in commercial use.
Earlier cars sit on the old four years or 80,000 km. A high-kilometre Tesla can be out of that general warranty with years left on its battery cover, so check the two separately.
What a Tesla still needs from a mechanic
There's no engine oil, spark plugs or timing belt, and Tesla doesn't set the kind of logbook service a petrol car has. That doesn't mean nothing wears.
Tyres and alignment do the most work. The car is heavy and the motors deliver their pull instantly. Suspension, wipers, cabin filters, air conditioning and brake fluid all need looking at too.
Brakes are the odd one. Regenerative braking (the motor slowing the car down) means the pads do less, so discs can rust and sliding parts can stick from lack of use, even though the pads look fine.
It's worth staying on top of. In a 2024 analysis of inspection results in Germany and Austria, TÜV ranked the Model 3 last among newer cars and said Tesla not requiring regular maintenance partly explains its failure rate. Those are European results, but a yearly look at the brakes, tyres and suspension is sensible here too.
Who should work on a Tesla?
Tesla runs its own service centres. Warranty claims, software faults and any question about the high-voltage pack start there.
Tyres, brakes, suspension, alignment and air conditioning don't have to. A local mechanic who works on EVs can do those, as long as they're trained and equipped for high-voltage cars. The orange cables are dangerous for anyone who isn't.
Under a national scheme, independents can buy the maker's service and repair information for cars made from 2002 onwards. Whether a particular workshop has it for Tesla is a fair thing to ask.
Tell us the model and what the car's doing. A local mechanic who specialises in your car.
What you can check on a Tesla
You can
- Photograph any warning on the screen, with the kilometres showing.
- Find the delivery date and compare it, and your kilometres, with the warranty limits.
- Check tyre pressures and tread with the car parked.
Leave to the mechanic
- Anything on the high-voltage pack or its orange cables.
- Brake, suspension and wheel alignment work.
- Testing the low-voltage battery, and replacing it if it's worn.
If it were our Tesla
We'd read the warning, work out which battery it means, and check the date and kilometres against the warranty. If there's any chance the high-voltage pack is covered, we'd put it to Tesla in writing before anything else. For the rest, we'd ask a local mechanic who works on EVs for a written estimate that names the fault, the parts, and whether a repair is possible instead of a replacement.