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TPMS Yokohama - Magneti Marelli

The mandatory changes introduced by the TPMS on all new cars, imposes upon tire dealers an increasingly specialized and qualifying professional growth

Duilio Damiani

What will the future bring? Considering the rather uncertain present, it might sound like trying to read tea leaves. We can anticipate something though; analyzing the situation recently created as a result of the introduction of new tire pressure monitoring systems, commonly referred to as TPMS, mandatory on all vehicles currently traded in Europe since last November ( in the US this has been so since 2007), there is no need of a crystal ball to predict how this will change the sector in the years to come, with tire dealers ready to adapt to the maintenance procedures, and above all, by the introduction of these new elements.

Not just compressors and pressure gauges, mastic and weights, the tasks of the tire dealer will have to include working on valves and ECU settings, with appropriate diagnostic tools, something that up until recently were the prerogative of garages and repair shops.

Tire dealers too reluctant to perform the necessary changes will soon have a clientele increasingly made up of older vehicles, being compelled to redirect newer vehicles - over 1.3 million vehicles sold on average every year - to other tire shops or garages ( also car repairers now increasingly complement their traditional services with tire replacement services) properly equipped and able to intervene on a TPMS.



Direct or indirect

On Pneurama a lot has been written already, but we would like to dispel any lingering doubts. The current legislation (Regulation No. 661/2009 of the European Community), which defines the requirements for motor vehicles approval, provides for tire pressure monitoring systems as standard equipment "... able to issue a warning to the driver if a pressure loss is detected in any of the wheels ", without specifying in detail the technology to be adopted. Thus two different tire pressure monitoring systems are currently becoming very popular, the indirect and direct systems. The first, less precise and functional, detect a pressure drop in the tire using the sensors of other electronic systems such as ABS and ESP, by monitoring the different rolling radius of an under-inflated tire, detecting any tire with a diameter reduction due to a lower internal pressure. When the system detects a lower pressure in one or more tires, starting from approximately a 30% drop, a warning light on the dashboard indicates the problem. This system, allowed in Europe but not for example by the NHTSA (National Highway Transport Safety Administration) in the North American market, although being the most economical for the user, is not able to detect the actual internal pressure, being limited to merely comparing the diameter of the wheels, ineffective, for example in the case of a slight loss or a simultaneous deflation on all wheels. True, in maintenance operations this spells very little changes for the tire dealer, since there aren’t any foreign element to the wheel, with the exception of a dedicated ECU that needs a correct reset mode.


The direct system, more complex but more accurate, places a sensor in each wheel, and is therefore able to instantly detect the actual pressure (as well as temperature) of each tire – and the spare tire too - reporting any change in the set values, starting from a 2% difference. The information collected by the sensors are transmitted at regular intervals to the ECU at the frequency of 433/434 MHz by one or more transmitters generally positioned under the wheel arches, or exploiting the vehicle’s hands free systems, if any, used for opening doors without using the key.

Even in the absence of air pressure loss, holes, or damages, the sensors still require constant controls to prevent malfunctions, using the correct spare parts and reviewing the settings whenever it becomes necessary. Salinity, weather conditions, shocks and humidity require routine maintenance, periodically checking the efficiency of the sensors even during seasonal tire replacement, or planned interventions, recommended at least every six months.


TPMS sensors, whether original or universal, whose complete replacement is normally required every 5 years or after 160,000 km, are currently made up of a valve / sensor, which can be of the Snap-In kind (with a rubber stem ) or Clamp-In (with metal stem), mandatory on vehicles with speeds exceeding 210 km / h. Those with a fixed angle are matched by others with a variable angle (which can bend up to 10 °), to better adhere to the inner profile of the rim avoiding possible damage during the mounting of the tire. During inspections or regular controls, technicians could consider replacing the rubber seal, the metal ring seal, the outer collar, the pin and of course the cap common to all inflation valves.

Currently each sensor, OE or aftermarket, can have a retail cost of between 40 and 200 euro, a figure certainly not negligible when multiplied by four. It is, however, an evaluation destined to be proportionally reduced as these sensors will multiply and spread for years to come. Not only that, the current systems could soon be displaced by a future generation of sensors, to be applied inside the tread, probably not fed by a battery anymore but by a micro piezoelectric generator stressed by the vibrations of the wheel.

Less revolutionary is the future of programming and diagnostic equipment, such as Magneti Marelli’s TPMS Connect EVO, which already today, via a multi-database, can quickly identify the specifications of each car to match the correct software - the communication protocol - to programmable sensor (OE do not require programming).



The Yokohama - Marelli synergy 

But practically speaking, what difference does it make for the tire dealer? We received the opportunity for a comprehensive study on the subject at the introductory course organized at the headquarters of Yokohama Italy, in Carpenedolo (BS), in collaboration with managers and trainers from Magneti Marelli After Market Parts and Service, Magneti Marelli’s specialized divisions in the distribution of spare parts, automotive systems and training services in the field of independent multi-brand car repair shops. The synergy between the two companies will produce a series of training courses, organized at agreed prices, and addressed to members of Yokohama’s CDG and CDG One networks, which will take place periodically throughout Italy followed by experts from both companies. This partnership will also lead to the supply of all the equipment and devices aimed at operating on direct tire pressure monitoring systems, of which Magneti Marelli has a large catalog with appropriate tools for every level of intervention.

The meeting between Yokohama and Magneti Marelli prompted the natural interest between the two companies, intending to establish a partnership that will provide valuable support to the industry, not only with regard to components, but also aimed at the professional update of tire specialists preparing them to deal with the cars of today and those of tomorrow.

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