Toyota Yaris tyre pressure warning light: how to reset it

On a Toyota Yaris you always set all four tyres to the correct cold pressure first, then reset the system in the way your car needs: on the Yaris and Yaris Cross that Toyota sells today the reset sits in a software menu on the Multi-info Display, while the third-generation Yaris that came before it uses a round reset button marked SET, low on the instrument panel below the steering wheel. There is no single Toyota button that every Yaris shares, which is why so much of the advice online sends drivers hunting for a switch their car was never built with.

Everything below is taken from Toyota's own material: the European Yaris owner's manual for the older car, and Toyota UK's published guide to the tyre pressure monitoring system for the current one. Both are named and linked so you can check them against your own car. Where Toyota does not publish a step for a particular generation, we say so rather than guess, because a wrong reset teaches the car that a soft tyre is normal.

Which tyre pressure system does your Yaris have?

Every Yaris in Toyota's current UK range uses a direct system, meaning a battery powered sensor sits inside each wheel and measures the air pressure for real. Toyota UK says direct systems are fitted to the majority of its current passenger car line-up, and that the only exception is the Proace Verso, which uses an indirect system reading wheel speeds through the ABS. Both the Yaris and the Yaris Cross are listed as direct.

The current-car rows come from Toyota UK's own guide to how TPMS works, which carries a model by model table of TPMS type, reset method and where the reset is found. The third-generation row comes from the European Yaris owner's manual (OM52G66E), published in 2016, which describes a system that uses tyre pressure warning valves and transmitters and shows the reset switch in its pictorial index. That is the edition we have checked, so if your third-generation Yaris is an early one, confirm the button against the handbook that came with the car.

Two things are worth knowing before you go looking. First, the monitoring system was not fitted to every older Yaris: the manual describes it throughout as equipment the car may or may not have, and Toyota UK notes that the technology only became a legal requirement for newly launched and factory updated passenger cars sold in Europe from November 2014. Second, Toyota UK's table covers the mainstream current range, so if you have a GR Yaris, read the handbook for that car rather than assuming. Our explainer on what the TPMS warning light means covers the difference between direct and indirect designs in more detail.

What does a steady light mean, and what does a flashing one mean?

A steady light means low pressure in at least one tyre. A light that flashes for about a minute and then stays on means the system itself has a fault, and no amount of pumping or resetting will clear it.

The Yaris owner's manual sets the two apart plainly. When the light simply comes on, it lists the causes as low inflation pressure from natural causes, such as slow air loss and temperature change, or a flat tyre, and the action as adjusting the pressure to the specified level, after which the light turns off after a few minutes. When the light comes on after blinking for 1 minute, the manual calls it a malfunction in the tyre pressure warning system and says to have it checked.

That one minute flash has a second trigger. If wheels are fitted whose sensor identification codes have not been registered to the car, the manual warns that after driving for about 10 minutes "the tire pressure warning light blinks for 1 minute and stays on to indicate a system malfunction". So a Yaris that started flashing straight after a wheel swap, a set of winter wheels or a new sensor is usually telling you about the registration, not about the air.

On the current Yaris and Yaris Cross you often get more detail than the symbol alone. Toyota UK points out that many current models with direct sensors can show which wheel has lost pressure on the Multi-info Display, so it is worth scrolling through the tyre pressure screen before you touch anything.

Where do you find the right pressures, and why does cold matter?

Resetting only works if the pressures are correct first, because both Yaris systems take whatever you have set as the new normal. Toyota UK's tyre pressure and size guide says the figures for your Toyota are listed in the vehicle handbook and in the driver-side door recess. On the third-generation Yaris the manual points instead to a label in the glove box. TyreSafe makes the same point more generally, listing the handbook, the inside of the fuel filler cap and the driver's door sill as the usual places.

We are not quoting numbers here on purpose. Yaris pressures change with engine, wheel size and how much you are carrying, so read them off your own car. What does transfer from one Yaris to the next is how you measure:

• Check them cold. The Yaris manual counts a tyre as cold if the car has been parked for at least 3 hours, or has not been driven for more than 1.5 km, which is about a mile. Anything warmer reads high.
• Never bleed air out after a drive. The manual states that a higher reading after driving is normal as heat builds in the tyre, and tells you not to reduce the pressure because of it. Let air out of a hot tyre and you will be driving on an underinflated one tomorrow.
• Use a gauge, not your eyes. The manual is blunt that it is difficult to judge inflation from appearance alone.
• Do all four. A reset with one soft corner simply stores the soft corner as the reference.
• Keep to a rhythm. The manual asks for a check at least once a month and says Toyota recommends every two weeks.

How do you reset the light on a current Yaris or Yaris Cross?

Through the screen, not a button. Toyota UK lists both the Yaris and the Yaris Cross as resetting through a software menu, and names the location as the Vehicle Settings menu on the Multi-info Display, the panel between the dials that you scroll with the steering wheel controls.

1. Park somewhere level and safe, and set all four tyres to the correct cold pressure for the load you are carrying.
2. With the car stationary, switch the ignition on.
3. Scroll the Multi-info Display to the settings, open the Vehicle Settings menu and find the tyre pressure entry.
4. Follow the instructions the car puts on screen. Toyota UK's wording is that once you have reached the right sub-menu, the instructions for resetting the system are shown within the main display.
5. Drive normally afterwards and let the readings settle before you decide it has not worked.

The menu names and the exact order of screens vary with trim level and with which display your car was built with, so use the handbook for your own registration rather than a video of someone else's car. Toyota publishes handbooks by vehicle through its owner's manuals service. If your Yaris has no Vehicle Settings entry for tyre pressure at all, that is a sign you are looking at a different generation or a different display, and the next section is the one you want.

For the models Toyota does fit with a physical button, its published instruction is short: turn the ignition on, then press and hold the TPMS button until the warning light flashes a couple of times and goes out, at which point the system has been reset.

Where is the reset button on a third-generation Yaris?

On the third-generation Yaris fitted with the system, the tyre pressure warning reset switch is a small round button carrying the tyre symbol and the word SET, set low into the instrument panel below the steering wheel. That is where the owner's manual's pictorial index puts it, on both left-hand and right-hand drive cars, and the manual marks it as equipment only some cars have.

The manual's own initialisation procedure runs as follows:

1. Park the vehicle in a safe place and turn the engine switch to the LOCK position, or off on cars with smart entry and start. The manual notes that initialisation cannot be performed while the vehicle is moving.
2. Adjust the tyre inflation pressure to the specified cold level. The system will work from whatever pressure you set, so this is the step that matters most.
3. Turn the engine switch to the ON position, or to IGNITION ON mode on cars with smart entry and start.
4. "Press and hold the tire pressure warning reset switch until the tire pressure warning light blinks slowly 3 times."
5. Wait a few minutes with the ignition still on, then turn the engine switch to ACC or LOCK, or off on cars with smart entry and start.

When the manual says you must do this

The same section lists three occasions when initialisation is required: when rotating front and rear tyres that run at different pressures, when the inflation pressure is changed, and when the tyre size is changed. Initialising stores the current pressures as the benchmark.

How to tell it did not take

The manual gives two failure signs. If the warning light does not blink three times when you operate the switch, the setting has not been recorded. If the light comes on after blinking for a minute once you have driven for a while, the same applies. Repeated failed attempts are a reason to have the car looked at rather than to keep pressing.

Why does the light come back a few days later?

Most likely because air is still escaping. A reset hides the symptom for as long as the pressure holds, and a tyre losing air through a nail, a corroded valve or a poor seal at the rim will drop back below the threshold in days.

The Yaris manual's own instruction when the light appears is to inspect the tyre for a puncture first. If there is no puncture, it says to wait until the tyre temperature has fallen, check and adjust the pressures, and only then, if the light still has not gone out after several minutes, confirm the pressures are at the specified level and carry out initialisation. If the light keeps coming back, look for a nail or screw in the tread and listen for a hiss at the valve.

There are innocent explanations too. Cold weather pulls pressure down as the air contracts, which is why the first frost of autumn lights up so many dashboards, and our piece on tyre pressure in cold weather explains the effect. A fitted spare will also keep the light on: the manual points out that the spare carries no sensor, so the warning stays until the repaired wheel goes back on.

The manual also lists conditions that stop the system working properly at all, including tyres without sensors fitted, sensor identification codes that have not been registered, an inflation pressure of 500 kPa or higher, nearby equipment using similar radio frequencies, a window tint that blocks the signal, heavy snow or ice packed around the wheels and wheel housings, non-genuine wheels, and tyre chains. Several of those clear themselves once the condition passes.

What happens to the sensors when you change tyres or wheels?

They need attention every time, and sometimes they need a dealer tool. Toyota UK's guidance is that the condition and function of the valve and sensor assembly should be checked each time the tyres are replaced, using a physical inspection and electronic diagnosis. It also notes that the sensor's built in battery lasts around ten years and cannot be replaced, so the diagnosis is what tells you whether to renew the unit while the tyre is off.

Even when the sensor body is being kept, Toyota UK advises replacing the parts exposed to the weather, naming the grommets, washers, collars and cores, because those are what deteriorate and start the slow leaks. That is ordinary good practice at a tyre change rather than an upsell.

Registration is the part people get caught by. The Yaris manual is clear that each valve and transmitter carries a unique identification code, and that when one is replaced the new code has to be registered to the car, which it asks owners to have done by an authorised Toyota dealer or repairer or another suitably qualified and equipped professional. Toyota UK adds that a car with direct sensors will only talk to one set of wheels at a time, so anyone swapping between summer and winter sets needs the control module reprogrammed through the vehicle's OBD port by a qualified technician. We are straight about that limit: our mobile fitters inspect the valves at a tyre change and will tell you if the warning points to a sensor, but coding a new sensor identity into the car is dealer-level work. Our guide to TPMS sensor replacement goes through what is involved.

Is it safe to drive, and will the light fail an MOT?

Treat it as a reason to stop and look, not a reason to carry on. Toyota UK's advice is to pull into a safe area and visually check the tyres, and if one looks deflated but undamaged, to reinflate it and reset the system. Stop straight away instead if the steering pulls, you hear flapping or rumbling, or a tyre is visibly flat, because driving on a deflated tyre wrecks the sidewall quickly and turns a repairable puncture into a new tyre.

On a motorway, do not stop on the carriageway to investigate. If the car still handles normally, slow down, leave at the next junction or services and check the tyres somewhere safe; if it does not, pull onto the hard shoulder or into an emergency area and get everyone out on the verge side and behind the barrier. If you feel in danger, call 999, and National Highways can be reached on 0300 123 5000.

The MOT angle is real. The DVSA MOT inspection manual lists a tyre pressure monitoring system that is malfunctioning or obviously not working as a major defect for cars first used on or after 1 January 2012, which takes in the third-generation Yaris from its first full year on sale and every Yaris since. Toyota UK puts it just as directly, warning that a vehicle cannot pass its annual MOT test with the warning light on, including when the light is lit only because a spare without a sensor is fitted. Our page on MOT tyre checks covers the rest of the tyre items.

One more thing the manual is firm about: the system does not replace checking the tyres yourself. It warns that a monitoring system will not save you from a tyre that is worn, damaged or slowly going down between warnings.

When should you get a mobile fitter to look at it?

Call rather than pump it up again if any of these apply:

• the light returns days after you corrected the pressures and reset the system
• one tyre keeps going down, or you can see a nail, screw, cut or bulge
• the light flashes for about a minute and then stays on
• the warning appeared straight after new tyres, a wheel swap or a set of winter wheels
• the tyre is too soft to drive on safely

Rescue Tyres is a fully mobile tyre service covering London and the Home Counties from one base at Brent Cross, NW2; further out, call and we will tell you whether we can take the job. Our fitter checks all four pressures against your Yaris's own figures, inspects the tread, sidewalls and valves, and carries out puncture repairs to BS AU 159 where the damage falls in the repairable area. If the tyre cannot be repaired we source a replacement in the correct size, including run-flat and EV fitments, and fit and balance it where the car is parked. If the problem turns out to be a sensor rather than the tyre, you will be told that plainly, along with what can be done at the roadside and what needs a dealer tool.

The price is confirmed on the call before any work starts, and a realistic arrival time is agreed on the call. Phone or WhatsApp 07473 720871, or book online.