Toyota Mirai Problems Common Issues and Repair Costs

September 26, 2025September 26, 2025 @CarExamer 5 Views 0 Comments

The Toyota Mirai is a hydrogen fuel cell electric car. It produces electricity inside a fuel cell stack by combining hydrogen with oxygen from the air. This powers an electric motor, and the only exhaust is water. The car appeals to drivers who want zero emissions but quicker refuelling than battery EVs. However, it comes with its own set of problems and some expensive repair costs.

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Common Problems with the Toyota Mirai

1. Fuel cell system failures
Owners have reported sudden power loss, weak acceleration, or warnings that the car is in reduced power mode. These problems often come from faults in the fuel cell stack or related electronics.

2. Recall for voltage spikes
In 2017 Toyota recalled nearly 3,000 Mirai cars worldwide. The issue was a voltage spike in the fuel cell boost converter. It was fixed with a free software update at dealerships.

3. Hydrogen refuelling problems
The biggest drawback of owning a Mirai in the UK is the limited hydrogen network. Many stations are offline, closed permanently, or too far apart to make long trips practical. This is often more of a problem than the car itself.

4. High hydrogen fuel costs
Hydrogen prices in the UK are high and unstable. When available, hydrogen has cost around £10 to £15 per kilogram. Since a Mirai takes about 5 kg to fill, a full tank costs between £50 and £75. In some areas, prices have been even higher, making it far more expensive per mile than charging a battery electric car.

5. Noises from hydrogen pumps
Some drivers report clicking or whirring noises from the hydrogen system when accelerating. This is normal for the high-pressure injectors and pumps, but it can be distracting.

6. Interior and electronics faults
A number of owners have complained about rattles, trim issues, or faults with the infotainment system. These do not affect safety but reduce comfort.

7. Cooling system leaks
The fuel cell produces heat, and the Mirai uses coolant to manage it. Leaks or pump problems can cause overheating and are costly if not fixed quickly.

8. Paint and trim wear
Early Mirai models have been reported with premature paint fading or chipping. This is cosmetic but lowers resale value.

Repair Costs and Maintenance in the UK

Routine maintenance
The Mirai has fewer moving parts than a petrol or diesel car. A basic service at a Toyota dealer is usually £120 to £250, depending on location.

Fuel cell and hydrogen system repairs
This is where expenses can become very high:

Replacing a fuel cell stack: £4,000 to £15,000+ depending on age and parts availability.
Power converters, injectors, or valves: £800 to £4,000.
Cooling system leaks and pump repairs: £400 to £1,500.
Software updates: often free if done under recall or warranty.

Fuel cost
A full refuel uses about 5 kg of hydrogen. At £12 per kg this means £60 for a full tank. At £15 per kg, it rises to £75 per fill. For comparison, charging a battery EV to cover the same mileage is usually under £20 on standard tariffs.