Tyre Pressure Sensor Replacement in London

What's included

• Every sensor read with a TPMS tool first: ID, pressure and battery state, so only the faulty one is changed
• Tyre broken down on the van and the failed sensor removed from inside the rim
• A sensor matched to your car from the registration, either programmable or the original type
• New seal, nut, valve core and cap fitted with the sensor, tightened to the maker's figure
• Sensor programmed and the car taught its ID by tool, by its own sequence or by a test drive
• Wheel balanced on the van before it goes back on the car
• All four tyres set to the pressures on your door sticker and the light checked out
• Indirect systems reset, and sensors moved across when new tyres or wheels go on

Why choose Fast Tyre for TPMS sensor replacement

A dead sensor is a job a garage does with the car in its workshop, so most people lose half a day driving there and waiting. The car does not need to go anywhere. Our van carries the tyre machine, the balancer and the TPMS tool, so the tyre comes off, the sensor goes in and the relearn is done on your drive or in your work car park. You pay nothing extra for an evening, a weekend or a bank holiday, and the cost is quoted on the phone before anyone sets off.

How tyre pressure sensor replacement is done at your car

The light on the dash tells you something is wrong but not which wheel or why. This is the order we work in:

• Tell us what the light does. A light that flashes for about a minute when you start the car and then stays lit usually points to a sensor or system fault; a steady light is more often a soft tyre. A "sensor not detected" message narrows it further. Your registration lets us confirm the right sensor before we leave.
• Read all four sensors. The TPMS tool wakes each sensor in turn. The one that will not answer, or reports a low battery or a nonsense pressure, is the one that comes out. If all four answer and the pressures are right, the fault is elsewhere and we say so rather than sell you a sensor.
• Swap the sensor and service the valve. The tyre is unseated with the sensor kept clear of the bead breaker, the old unit taken off, and the new one fitted with fresh sealing parts. The tyre is refitted, inflated and balanced on the van.
• Relearn and prove it. The car is taught the new ID in the way its maker requires, then we check every position is reporting and the warning has gone before we hand back the keys.

Direct or indirect: which TPMS does your car have?

There are two kinds of tyre pressure monitoring, and only one of them has sensors to replace. A direct system has a small battery-powered sensor inside each wheel, usually built onto the back of the valve, which measures the air pressure and radios it to the car. If you can see each tyre's pressure on the dash, or the valve on an alloy wheel is metal and held by a nut, you almost certainly have direct TPMS.

An indirect system has nothing in the wheel. It uses the ABS wheel-speed sensors and spots a tyre that has gone soft because it turns slightly faster than the others. Indirect systems never need sensors replacing, but they do need recalibrating after pressures are adjusted, tyres are changed or wheels are swapped round, and they will give a false warning if they are reset with a tyre already low. If your car is indirect we set the pressures and run the reset, which is often all that was needed.

Not sure which you have? Read what the tyre pressure warning light means first; it walks through the symbols, the flashing and steady patterns and the quick checks you can do before calling anyone.

Signs a tyre pressure sensor has failed

Sensors are sealed units. The battery is moulded inside and cannot be changed, so when it goes the whole sensor is replaced. Batteries typically last 5 to 10 years, less on cars that cover a lot of miles because the sensor transmits more often. The signs are usually:

• a warning that flashes at start-up and then stays on, even with every tyre at the right pressure
• a message such as "tyre sensors not detected", "TPMS fault" or "check tyre pressure system"
• one wheel showing dashes, or no reading, on the pressure display
• a warning that comes and goes on cold mornings before going on for good, which is a battery near the end
• the light appearing straight after a tyre change, where a sensor has been cracked, or a sealant can from a puncture kit has clogged its pressure port

Because the four sensors on a car were fitted together and their batteries age together, one failing is a fair sign the rest are not far behind. We read all of them and tell you how each one stands, so you can decide whether to do one now or the set at once.

Programmable sensors and the relearn

A replacement sensor has to talk to your car in the right language, on the right frequency, and the car has to know its ID. There are two routes. An original-equipment sensor is the same part the car left the factory with. A programmable sensor is an OE-equivalent unit that arrives blank and is loaded with the protocol for your make and model by the TPMS tool; on many cars it can also be given the old sensor's ID, so the car accepts it without noticing a change.

Where the ID is new, the car has to learn it. Makers use three methods: a tool relearn through the diagnostic port under the dashboard, a stationary relearn where a set sequence of ignition, button and pedal presses puts the car into learn mode, and an automatic relearn where the car picks up the new sensor during a short drive above a set speed. Some cars need two of these together. We follow the method your car calls for, which is the step most often skipped when a light reappears a day after a sensor was fitted elsewhere.

TPMS valve service at every tyre change

On a direct system the sensor's valve stem is also the tyre's valve, so it carries the same sealing parts as any valve: a rubber seal or grommet against the rim, a nut on metal clamp-in stems, a valve core and a cap with its own seal. Sensor makers treat these as one-time parts, to be replaced each time the tyre comes off, because the seal flattens to the shape of the rim and the nut's thread suffers each time it is torqued. Aluminium stems also need a nickel-plated core and the correct nut, or the two metals corrode together and the stem can seize or snap.

That is why a TPMS valve service goes in with every tyre we fit on a sensor wheel, and why an old sensor with a corroded stem is better replaced while the tyre is already off. Our tyre valve replacement page covers ordinary rubber valves on cars without sensors, and the guide to snap-in, clamp-in and TPMS valves shows how to tell yours apart.

Is a TPMS fault an MOT failure?

Yes, on most cars. The MOT includes the tyre pressure monitoring system on passenger cars first used on or after 1 January 2012, and a system that is malfunctioning or obviously not working is a major defect, which is a fail. The tester is looking for a fault warning, not a low tyre: a light that is simply telling you a tyre needs air should go out once it is inflated, and if it is not clear which the light means the tester can add an advisory instead. Vans are not tested on TPMS at the MOT, though a van with a dead sensor has still lost its early warning of a puncture.

If the MOT is coming up and the light is flashing at start-up, book the sensor in first. It is far simpler than failing, fixing and returning for a retest. If the warning came on at speed, read what to do if the tyre pressure light comes on during a motorway drive: get off at the next exit or call 999 or National Highways on 0300 123 5000 if you are stranded, and we come once the car is off the motorway.

Mobile TPMS sensor replacement near you

We replace tyre pressure sensors at the car anywhere we cover, across London and the surrounding counties, around the clock. If you were searching for TPMS sensor replacement near me, the van comes to you instead. The same visit can cover new tyres fitted at your home or work, with the sensors moved across and serviced, or a puncture repaired where the tyre has lost air. Changing over to a second set of wheels without sensors? The seasonal tyre swap visit can fit and programme a set at the same time. If you are not sure whether the tyre itself needs replacing, see tyre replacement near you.

TPMS Sensor Replacement, frequently asked questions