TPMS Servicing & Replacements

What is a TPMS?

TPMS stands for “Tyre Pressure Monitoring System” and this is a special type of electronic tyre valve designed to monitor the tyres pressure on all 4 of your pneumatic tyres on your vehicle. The real-time tyre pressure data collected by the TPMS monitor equipment is then wirelessly transmitted to the vehicle onboard display to report to the driver that the tyres are properly inflated or to alert when the tyre pressures are too low or too high. Garages can also connect to the TPMS sensor on customers vehicles to check tyre pressures before or after replacing or inflating tyres, often used after tyre replacement, balancing or prior to doing vehicle wheel alignment.

The Law on TPMS:

Since November 2012, all-new type class M1 passenger vehicles (under 3.5 tonnes and up to 8 seats) must be fitted with TPMS as standard. From November 2014, all new passenger vehicles must be, by law, factory fitted with TPMS. Cars registered after January 2012 must have TPMS functioning to pass MOT’s.

Understanding Types of TPMS

There are two main types of TPMS system, Indirect TPMS Systems & Direct TPMS System.

Indirect TPMS Systems

Indirect TPMS systems use the ABS sensors on the vehicle. Tyre pressure isn’t directly measured but is calculated by assessing the rotational speeds of each tyre.

Pros:

  • The technology is already installed

  • Indirect TPMS doesn’t require servicing

  • Won’t be damaged when removing tyre

Cons:

  • This type of TPMS is not known to be very accurate.

  • It can be slow to react.

  • Indirect TPMS doesn’t notify if all 4 tyres are under inflated

  • Puncture after parking cannot be identified

Direct TPMS System 

The sensor is fitted in each wheel/attached to the bottom of the valves. The vehicle ECU will then get data directly from each individual sensor.

Pros:

  • Direct TPMS systems are fast reacting

  • Very accurate

  • Will detect a puncture, even after parking

  • Detects a slow leak

  • Able to specify locations of pressure issues

Cons:

  • Requires maintenance (servicing or a new sensor required after every tyre removal is recommended)

  • Requires specialist tools & equipment

  • TPMS sensors can be damaged when removing or fitting a tyre