Tyre pressure decreases over time, this is a natural phenomenon. Tyre pressure also varies depending on ambient temperature. Driving on tyres with tyre pressure that is too low could result in the tyres overheating and being damaged. Tyre pressure affects travelling comfort, road noise and driving characteristics.
Check the tyre pressures monthly. Use the recommended tyre pressure for cold tyres in order to maintain good tyre performance. Tyre pressure that is too low or too high may cause uneven wear on the tyres.
Warning
- Under-inflation is the most common cause of tyre failure. This may result in severe tyre cracking, tread separation, or “blow-out”, with reduced control of the vehicle, which may lead to increased risk of injury.
- Tyres with pressure that is too low reduce the load capacity of the car.
Cold tyres
The tyre pressure must be checked when the tyres are cold. Tyres are considered cold when they have the same temperature as the surrounding air. This temperature is normally reached when the car has been parked for at least three hours.
After having driven approximately 1.6 km (1 mile) these tyres are considered as warm. If you have to drive further than this to inflate the tyres, first check and record the tyre pressure. Then inflate to a suitable tyre pressure when you arrive at the pump.
When the outside temperature changes, the tyre pressure also changes. A decrease in temperature of 10 degrees causes the tyre pressure to decrease 7 kPa (1 psi). Check the tyre pressure regularly and adjust to the correct pressure, which is specified on the car’s tyre information decal or certification label.
If you check the tyre pressure when the tyres are warm then you must never release any air. The tyres are warm due to driving and it is normal for the pressure to increase above the recommended pressure for cold tyres. A warm tyre with tyre pressure equal to or below the recommendation for cold tyres may have a pressure that is far too low.
Adjusting tyre pressure
Tyre pressure decreases over time, this is a natural phenomenon. The tyre pressure must therefore sometimes be adjusted in order to maintain the recommended tyre pressure.
Use the recommended tyre pressure for cold tyres in order to maintain good tyre performance and even tread wear.
Note
To avoid incorrect tyre pressure, the pressure should be checked on cold tyres. “Cold tyres” means the tyres are the same temperature as the ambient temperature (approx. 3 hours after the car has been driven). After a few kilometres of driving, the tyres warm up and the pressure increases.
Remove the cap from the valve on one tyre and then press down the tyre pressure gauge firmly onto the valve.
Inflate the tyres to the correct pressure, see the decal on the door pillar on the driver’s side showing the recommended pressure for factory fitted tyres.
Refit the dust cap.
Note
- After a tyre has been inflated, always refit the dust cap in order to avoid damage to the valve from gravel, dirt, etc.
- Only use plastic dust caps. Metal dust caps can rust and become difficult to unscrew.
Check the tyres visually for any implanted nails or other objects that could puncture the tyre and cause leakage.
Check the sidewalls for any cavities, cuts, bumps or other irregularities.
Repeat this for all tyres, including the spare tyre.
Note
If you have over-inflated, release air by pressing in the metal pin in the centre of the valve. Then check the pressure again using the tyre pressure gauge.
Some spare tyres require a higher tyre pressure than other tyres. Check in the tyre pressure table or on the tyre pressure label.
Location of tyre pressure label
The tyre pressure label on the driver’s side door pillar (between frame and rear door) shows which pressures the tyres should have at different loads and speed conditions.
The decal displays the designation for the factory-fitted tyres on the car, as well as load limits and tyre pressure.
Note
It is not intended that the decals illustrated in the owner’s manual should be exact replicas of those in the car. They are included to show their approximate appearance and locations in the car. The information that applies to your particular car can be found on the decal on the car.
Improved fuel economy with ECO pressure
For a light load (max. 3 people) and a speed of up to 180 km/h (112 mph), the ECO pressures can be chosen for more economic electric consumption. However, the lower comfort pressures are recommended instead if improved noise and travelling comfort are desired.