Making Sense of Tyre Sensors

So a strange looking light has appeared on your dash, or your car is giving you a 'LOW PRESSURE' alert. What does it all mean and how does it work?

Well, a few years ago it was made mandatory for all passenger vehicles sold in the EU to have a Tyre Pressure Monitoring System fitted. This was designed to reduce harmful carbon emissions and of course road safety (yes, low pressures will have a dramatic effect on the amount of fuel you burn and wear your tyres out way faster too!!).

SO there's a couple of tyre monitor systems out there. One uses a special tyre sensor fitted to the valve in the wheel to report back to a computer in the car the exact and live tyre pressures - usually in psi (pounds per square inch). If the pressure falls below a preset figure you'll get a warning to check the pressures or look for a possible puncture or other issue.

The other tyre monitor system measures the amount of rotations each wheel takes over a set distance. If this continues to alter, you're alerted to a potential issue by means of a warning light or alarm etc. This system doesn't usually tell you which tyre is at fault though. When a tyre loses pressure, it gradually loses it rolling circumference and this is what is being measured and reported on.

So the first tyre monitoring system mentioned has quite a number of working parts - including a battery powered tyre sensor in each wheel. Connected to this is a special TPMS valve stem - which has serviceable components. A new car will give you around 7-8 years of TPMS battery life. The valve assembly including air seals will last around half of this time before potentially leaking air.

What does this mean for you?

Actually, you could just not concern yourself with it all and simply wait for it all to fail before thinking about fixing it - then pick up quite a tab all at once.
If you're unlucky enough to have to go to a main dealership you can expect to be paying around £185 per valve plus a hefty reprogramming fee too.
Or.... have the TPMS valve components regularly checked and serviced (it costs on average about £8 to change a whole valve stem (not the sensor part). At the same time, the sensor battery level can be checked and when its showing at end of life, can be replaced at less than half the above cost per unit!

While a TPMS valve looks like a solid object (unlike it's rubber encased alternative), it does have small seals inside (not the cute type!) which will compress and deteriorate with age. At present most motorists are completely unaware of the serviceable nature of these valves. The great thing is that they will generally last longer than a conventional rubber one - but they still need attention!

Hometyre techs carry all of the necessary gadgets and gizmos to replace and repair everything TPMS related! Instead of having to reprogram new tyre senors to your car, when the battery gets low we simply scan the unique transmission codes and import them into brand new blank sensors and off you go! All a bit confusing? Call us on 03334445454.