TPMS or Tire Pressure Monitoring System is a technology that ensures the cars are being driven on correctly inflated tyres to reduce the dangers of driving on low pressure or flat tyres.
Many newer vehicles come fitted with a TPMS system as standard however you may find that if you have an older vehicle that is not the case. In the US it has been a mandatory requirement since 2007 to have a TPMS system fitted in vehicles.
The European Union was a bit slower in implementing this requirement. The EU have made it a requirement for all vehicles manufactured in the EU from November 2014 to be fitted with a TPMS system.
In the UK since 2015 if you have a TPMS warning light displayed during a MOT Test on your dashboard for any car manufactured after 2012 it will lead to a MOT test failure.
If you have a manufacturer installed system you maybe thinking I don’t need to do anything. However not all standard system great, many will just display a flashing TPMS light on the dashboard but give no other information such as which tyre you have a problem with. In such a scenario you would have to go around each individual tyre, remove the valve caps and use a suitable tyre pressure gauge to check the pressure, not convenient especially if the weather is not to great. So even if you have a pre-installed system you may want to add an aftermarket TPMS system.
If you want to add this feature to your vehicle then you will have to install a central receiving unit and sensors to measure the pressure in the tyres so that the driver can be alerted whenever pressure in the tyres is reduced. Usually an indication of dangerously under inflated tyres or a puncture.
Types of TPMS
If your thinking of modifying your tyres with TPMS then there are two types of tyre pressure monitoring systems (TPMS) that are available in the market.
In the first type sensors are installed into the tyres as part of their valve system and in the other type sensors are installed in the caps of valve stem. Both these types of systems are effective at monitoring tyre pressure if installed correctly.
If you want to carry out the project at home then you will find it easier to install the sensors in the caps of the valve stem then within the valve system. These cap based systems can also be used in conjunction with a manufacturer installed TPMS system.
Installing the TPMS Caps
As mentioned earlier using this type of system is perfect for anyone who wants to do the job themselves and save on going to a dealership or local mechanic.
You will usually find that the kits will include a monitor that goes into the car on the dashboard. These monitors can be powered using the 12V cigarette lighter. If you have more then one electrical item you want to power through the 12V outlet then you can buy a 12V power splitter. If you want a cable free cabin then there are some kits that have a monitor that is solar powered.
Apart from the monitor you will then generally have 4 cap pressure sensors, one for each tyre on the car. Before you go along installing the sensors make sure that all the tyres are at the same pressure. We have written an article on how to find your cars correct tyre pressure.
Once your happy with the tyre pressure the next step is attaching the sensor to the valve stem. Each sensor should be labelled with the corresponding tyre it should be connected to so for instance the front right sensor may be labelled with FR, if unsure check the manual that came with the kit.
The sensor will usually come with a dust cap, security nut and the sensor. Place the dust cap on first then the security nut and finally screw on the sensor. Try to avoid any cross-threading and tighten the sensor on the stem until you hear no air leaking out.
You then need to tighten up the locking nut and sensor to ensure that no once can steal the sensor. You will need a suitable tools, usually supplied in the kit to do this. If you need to add air to your tyres once the TPMS system is installed then you will need to have these tools at hand so ensure you keep them in a safe place. Finally slide the dust cover over the back of the locking nut and sensor.
You then have to repeat this process with the rest of the tyres. Once completed check the monitor you have installed in the car. Every system is different, some will provide audible alerts if the tyre pressure falls below a certain level. Be aware that tyre pressure can be affected by temperature. Read our article on how tyre pressure can be affected when tyres are hot or cold.
After reading this installation method I hope it makes it easier for you to install a Cap TPMS system.
Installing the TPMS inside the valve
If you want to install the sensors of TPMS inside the valve of the tyres yourself then you will have to release the air of all of your tyres and break their beads to remove and replace the valve stems of all the tyres.
To make life easier you could take your tyres to a tyre shop to have a technician break the bead and then you could go ahead and replace the valves. The cost of them breaking the beads and then refitting the tyre around the wheel/alloy will vary but typically costs between £5 – £10 per tyre. Although this is an added expense it may save you some time learning how to break the tyre bead.
If your planning on breaking the bead your self there are a number of videos and how to guides available on the internet. The techniques vary and will require skill and practice to remain safe. Tools that may be useful include: tyre levers, scissor jack, valve core tool, floor jack, ratchet tie down strap.
The first part of the process will involve using the valve core tool to remove the valve to allow all the air out of the tyre.
The next step will vary based on how you want to break the bead. The following video show how you can use an everyday floor jack, a ratchet tie down strap and a valve core removal tool to remove the bead quickly.
The rubber stem should be pulled through the hole in the tyre that you removed the old valve from. You can use a valve stem pulling tool to to ensure that the rubber stem has been pulled all the way through. Do this whilst the TPMS sensor is not attached to the stem.
Once the rubber stem is correctly seated in the wheel use a suitable torx screw to connect the sensor to the stem.
If your dealing with an aluminium made clamp in sensors you must install the hex nut and ensure it is tightened to the recommended torque settings.
The last step involves installing a new valve core in the stem, ensure it is tightened to the correct torque setting using an inch/pound torque wrench. Then you need to inflate the tyre and check for any air leaks.
Cost of installing TPMS
The cost of installing TPMS can vary depending upon the quality and types of sensors as well as how they are installed. If you need to replace your manufacturer installed system at a dealership then it could cost your £400-£500 in the UK and $800 in the US. Aftermarket kits can cost between £50 – £150 depending on the brand and features that you pick.
Troubleshooting TPMS
Does warning light of TPMS remain on?
Reason:
It can be due to aging of your vehicle or low pressure of your tyres. Damaged tread, rim or sidewalls of your tyres can be also be a valid reason for glowing warning light of your TPMS.
Solution:
While adjusting or replacing the sensors either you will have to re-program the sensors or put the vehicle on learning mode. In some cases, vehicles adjust the sensors automatically just by rotating them whereas in some cases you will have to program them or make them relearn manually.
The sensor of spare tyre does not work properly.
Reason:
People either forget to install sensor in the spare tyre or the sensor in the spare tyre is not activated.
Solution:
While installing TPMS sensors in all the tyres of your car you should also remember to install it in the spare tyre. While servicing the TPMs of your car tyres you should also get the spare tyre serviced properly so that whenever you use it you can get signals when the pressure in that tire is reduced.
Summary
The installation of TPMS in all the tyres of your car can ensure the safety of your tires as well as improving the fuel economy of your car. They can also prevent the chances of accidents by alerting the driver about the pressure in the car tyres so that he can maintain them well in time.
