Reset the Tyre Pressure Monitor (TPMS)

If the tyre-pressure warning has come on in your Subaru WRX / WRX STI (2015–2021) — the VA — it is almost always the car flagging a tyre that reads low against its target, not a mechanical fault. On a performance saloon the light often turns up after a cold morning, after a tyre has lost a little air over a few weeks, or straight after you have reset the pressures or changed a wheel and the system is still looking at the previous figures. Drivers who scrub the outer edges on track days or corner hard also see it when pressures shift. Set the four pressures correctly, drive far enough for the WRX to re-read them, and the warning goes out by itself. Here is how to do it cleanly.

How the WRX watches your pressures

The car monitors each wheel and raises the warning when a tyre falls roughly below the figure on the driver’s door-pillar placard. This generation clears the light from the corrected pressures rather than from a dashboard button-press, so there is no reset menu to find — the reset is simply getting all four pressures right and letting the system read them on a short drive. On the WRX it is worth being precise: the low-profile tyres show pressure changes quickly, so a slightly soft corner is easy to trigger.

First, a Few Checks

• Set the tyres cold — parked at least three hours, or driven under a mile. A hard drive warms the tyres and makes them read high, hiding a low one.
• Use the placard figure in the driver’s door shut, not the maximum printed on the tyre sidewall.
• Do every corner with an accurate gauge, including the tyre that set the light off.
• Don’t skip the spare if a full-size wheel is on the ground.
• If you run track-day pressures, remember to return to the road figures before expecting the light to settle.

When to Reset

• After checking or adjusting the tyre pressures.
• After changing wheels or tyres, or fitting winter wheels.

Resetting the System

1. Park level and set all four tyres to the correct cold pressures (placard in the driver’s door shut).
2. Drive the vehicle for about 10 minutes at over 40 km/h (25 mph).
3. The system relearns the corrected pressures and the warning clears.

If the Warning Won’t Clear

• Recheck all four — one tyre a few psi low keeps the warning on even if the rest are perfect.
• Drive it longer — a short crawl may not give the system time to settle; a steady few minutes works better.
• Cold snap — a frosty morning drops pressure enough to trip the light; top up to the placard figure with the tyres cold.
• Track-day pressures — if you lowered or raised them for a session, set them back to the road figures.
• Space-saver fitted? The compact spare runs much higher than the road wheels, and the light can stay on until the normal wheel is back.
• Sensor fault — a wheel sensor with a flat battery or a damaged valve can hold the warning on with correct pressures. Any stored code can be checked on autodtcs.com.

Once It’s Done

With the pressures correct and a few minutes of driving done, the warning should clear and stay off for the rest of the journey. If it clears but comes back within a day or two, read that as a slow leak rather than an electronic fault and have the tyre inspected. A brief flash of the symbol at start-up that then goes out is normal self-test behaviour.

Frequently Asked Questions

How do I reset the tyre pressure light on a Subaru WRX?

This generation has no reset button. Inflate all four tyres to the cold pressures on the driver’s door-pillar placard, then drive for about ten minutes above 40 km/h. The WRX re-reads the corrected pressures during the drive and turns the warning off automatically.

My tyres are up to pressure but the light won’t go — why?

Usually one corner is still under target, or the drive was too short. Recheck each tyre cold with an accurate gauge, correct anything low, and take a longer run. If all four are genuinely right and it stays on, suspect a slow leak or a wheel sensor.

Does running track-day pressures set off the warning?

It can. If you drop or raise the pressures for a session they may sit outside what the system expects for road use, or read low once the tyres cool. Return the tyres to the placard road figures when cold and drive to let the WRX relearn them.

Do I need a diagnostic tool to reset it?

No — a routine reset needs only correct pressures and a short drive. A tool is only involved if a wheel sensor has been replaced and must be registered, or if you want to read a stored fault code.

Why does the light keep returning to the same wheel?

A warning that repeatedly comes back on one corner usually means a slow puncture — a nail, a kerbed or porous alloy, or a leaking valve. Recheck that tyre and inspect the tread and valve. Resetting again without fixing the leak only masks it.

Do I have to reset after fitting winter wheels?

Set the winter wheels to the correct cold pressures first, then drive so the system re-reads them; a full-size winter set behaves like the standard wheels once inflated properly. The temporary space-saver is the exception — it runs much higher and the light may stay on until the road wheel is refitted.

If the tyre-pressure warning came on alongside other dashboard lights, decode the stored trouble code on autodtcs.com before assuming it is only a pressure issue.