Indirect TPM systems really are worse than nothing
By David Shaw, ERJ staff
Brussels -- A high-powered report has concluded that indirect tyre pressure monitoring systems (TPMS) are at best useless, and at worst, worse than useless. In cars fitted with the indirect TPM systems, tyre condition was on average, worse than in cars fitted with no tyre pressure monitoring system. By contrast, cars fitted with direct tyre pressure monitoring systems showed substantially fewer under-pressure tyres than any other vehicles.
The GRRF TPMS Task Force, which represents car makers (through OICA), component suppliers (through CLEPA), tyre makers (through ETRTO) and transport officials, presented its data to interested parties in a 09 June conference call. The group aims to make its findings public on the UNECE website in the near future. ERJ has obtained a copy of the report prior to publication.
Chapter 2.2 of the report gives the results of a study by The Dutch ministry of Transport (RDW). RDW ran a survey on some 9000 vehicles, of which nearly 6000 could be identified by vehicle identification number. 5000 of these had no TPM system, 486 had a direct TPM system and 174 had an indirect TPM system (mainly BMW and Audi). The population of tyres at a pressure at least 0.5 bar under recommended value was around 8 percent where no tyre pressure monitoring system was present, but that rises to 9 percent on vehicles fitted with indirect TPM systems. The equivalent figure was just 2 percent in vehicles fitted with direct TPM systems.
Other data presented in the report shows that the presence of an indirect TPMS has virtually no effect on the condition of tyres on vehicles fitted with this system, compared with the absence of a TPMS system. The main exception to this is where pressure is down by 0.5 bar, the indirect systems were significantly worse than no TPMS system at all. In all cases, the presence of a direct TPM system showed marked improvements in tyre condition and hence both safety and fuel consumption.
This is an external link and should open in a new window. ERJ is not responsible for the content of external sites.
TPMS TF Conclusions V04.pdf
This article is only available to subscribers - subscribe today
Subscribe for unlimited access. A subscription to European Rubber Journal includes:
- Every issue of European Rubber Journal (6 issues) including Special Reports & Maps.
- Unlimited access to ERJ articles online
- Daily email newsletter – the latest news direct to your inbox
- Access to the ERJ online archive