Tesla Model S/X

Battery repair

Car repaired in 1-2 weeks
Basic repair 5 490 EUR (Warranty 1y/30 000km)
Basic repair with extended warranty 5 990 EUR (incl. maintanance after one year, warranty 2y/60 000km)

Basic repair includes:

  • Diagnostics
  • Checking and repairing of battery modules
  • Consumables and coolants
  • Necessary battery rust repairs
  • Transport to our workshop if necessary (charged separately)
  • Quick check of rear engine for fluid leakage
  • Pressure/leak test

By separate agreement:

  • Exchange of contactors
  • Battery case bottom dent repair
  • Rental car 49 €/day (Tesla Model 3)

More information about Tesla battery repair

What does it mean?

Before actually repairing the battery, the fault is diagnosed. Sometimes the vehicle can also be ‘paralysed’ by other faults in the high-voltage system – for example, the engine, battery heater, air conditioning compressor or interior heater can cause an insulation resistance fault when it breaks down, preventing the car from starting. However, just by looking at the alarms on the car’s display, you can be fairly certain that the battery needs to be repaired. Fault codes such as BMS_u029, BMS_u019, BMS_w017, BMS_f017, BMS_u018, BMS_f018, BMS_u025 and BMS_f107 indicate battery failure. BMS_f151 refers to a fault outside the battery.

When a battery failure is found to be probable, the car’s data is recorded on a tester, the battery is disconnected from the car, the battery is opened, the fault is located and repaired. The repair involves a full visual and, if necessary, electrical inspection of the battery, and replacement or cleaning of critical battery sealing and “venting” components. If the repair requires the replacement of battery cells or modules, the new (used) cells are adapted to the original battery pack of the car. The battery is assembled, reinstalled in the car, and a test drive and charge to determine the success of the repair.

A typical cause of battery failure is moisture accumulation in the battery. Moisture accumulates both through condensation and through valves in the battery skirts. The valves become dirty in dusty conditions and start to let moisture into the battery – temperature fluctuations contribute to this. Sometimes moisture also enters through holes in the fuse cover that have rusted through, or through bolt holes through the battery cover. Moisture trapped inside the battery causes oxidation – for example, circuit boards inside the battery break down. We can repair or replace these circuit boards with intact ones. In rarer cases, the battery cells themselves are damaged, requiring the replacement of the entire battery module.

In the case of an LDU (Large Drive Unit), we also check the motor encoder, i.e. the sensor at the end of the motor. These engines have experienced internal coolant leakage and a wet sensor is a sign of an incipient problem. If the sensor is wet or the engine shows other signs of leakage, we recommend servicing the engine as soon as possible.

How much does it cost?

A basic battery repair costs EUR 5490 (incl. VAT 24%). The repair cost includes the inspection of the battery according to the above process and the repair of faults, but not, for example, replacement modules. So if an entire battery module or other major parts (e.g. contactors) needs to be replaced, this will be charged separately. However, the price includes all the small items needed to repair the battery, such as adhesives, paints, replacement valves and components of the circuit boards to be repaired. Each repair will be approved from the customer by a written estimate of the cost before the repair work is commenced.

The repair must be paid for in full before the car can be collected and returned repaired. We are introducing a financing option through a partner, which means that the battery repair does not have to be paid for in one lump sum, but the cost of the repair can be spread over a longer period.

How long does it take?

Under normal circumstances, a battery repair service takes about a week. If parts such as the battery module need to be replaced, depending on the stock situation and availability of parts, you should allow a few weeks for repair. Tesla, for example, will take between one and two weeks to deliver new parts. The repair time estimate will be provided in the cost estimate.

The picture shows a badly oxidised battery module. Fortunately, this is a fairly rare occurrence.


Akkuauto Finland Oy grants a warranty of one year or 30 000km, whichever comes first. The warranty covers the repaired defect. If any other fault occurs within the warranty period, the warranty does not cover it. For an additional charge, a follow-up warranty can be purchased, which includes a service inspection one year after the repair.

Battery replacement

In some cases, the battery may be so badly damaged that it is worth replacing it. For example, if the battery needs to have several modules replaced, or if there is mechanical damage to the shell of the battery itself, you should buy another used battery and sell the intact modules of the old battery for other uses. An old car battery is not worthless, even if it is broken!

Third-party battery repair also means that the battery in question is no longer eligible as a replacement part for the car manufacturer.

A rusted out main fuse cover plagued the very early cars, before air conditioning condensation started to be diverted to a different location in 2014.

In more complex repairs we analyze the behaviour of the battery during charge and discharge.

The panel for rapidmate connectors will oxidise with age and road salt etc. At worst, moisture can sneak into the battery from here. If necessary, we replace the panel.

The valves on the battery skirts may start to leak moisture when they get dirty. We recommend regular cleaning of the battery skirts, this will significantly reduce the amount of moisture that accumulates in the battery.

New valves. In some cases the original valves can be cleaned, but in many cases they are replaced with newer versions.

A candy box with full of dirt collected from just one battery.

Contact us and ask more!