Interesting facts about tyre pressure monitoring systems (TPMS)
Tyre pressure monitoring systems (TPMS) are electronic systems designed to monitor the air pressure inside the pneumatic tyres on various types of vehicles. Tyre pressure loss is reported at an early stage so that increased fuel consumption as well as fast tyre wear can be avoided. Since November 1st, 2014, a TPMS is mandatory for all new registered vehicles.
Types of TPMS
A general distinction is made between two different types of tyre pressure monitoring systems - direct and indirect TPMS:
- Indirectly measuring TPMS (passive systems) use data from ABS or wheel-speed sensors to determine a loss of tyre pressure. If the difference between one and another tyre exceeds a certain tolerance, the monitoring system will indicate tyre pressure loss.
- Directly measuring TPMS (active systems) employ sensors within each tyre that measure the pressure and partially the temperature of the tyre. If a deviation outside a certain tolerance area is measured, the monitoring system will show the pressure loss.
Directly measuring TPMS are distinguished as follows:
- OEM sensors
The "classic" direct measuring TPMS are currently used as original equipment where the sensor is located behind the valve. The sensor contains a software protocol for a special automobile manufacturer.
- Universal sensors
These sensors provide the opportunity to replace OEM sensors. Universal sensors are "blank" and can be re-written and activated by a programming device for the given vehicle.
- Multi-brand sensors
These sensors are already programmed with various vehicle protocols, there is no additional programming work to do.
What has to be considered when you apply special wheels?
When applying special wheels you need an adequate TPMS if
- your customer´s car is affected by the EU regulation because of its year of construction and
- the vehicle is equipped with a directly measuring TPMS.
It is irrelevant if you use an OE-fit or an adequate (programmable) replacement sensor system.
For vehicles that are not affected by the EU regulation and for cars with indirectly measuring TPMS there will be no change to the previous legislation regarding TPMS.