Tyre pressure monitoring (TPMS) warning light
How it can appear on an MOT certificate
- “Tyre pressure monitoring system malfunctioning or obviously inoperative”
What it is
Many cars have a tyre pressure monitoring system (TPMS) that warns when a tyre is under-inflated. A warning light that stays on can mean low pressure or a fault in the system itself.
Why it matters
On cars first used from 2012 onwards, a TPMS warning showing a fault is an MOT fail. Under-inflated tyres wear faster, use more fuel and grip less.
What to check when viewing a car
Check that the TPMS light goes out after starting. If it stays on with correct tyre pressures, a sensor (often its battery) may need replacing.
Has the car you're looking at had this before?
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What the MOT categories mean
- Dangerous
- A direct and immediate risk to road safety, or a serious impact on the environment. The car fails and shouldn't be driven until it's repaired.
- Major
- It may affect the car's safety, put other road users at risk or harm the environment. The car fails and should be repaired straight away.
- Minor
- No significant effect on safety or the environment. The car passes, but it should be repaired as soon as possible.
- Advisory
- Something to keep an eye on that could need repairing in future. The car passes.
Related: tyres and wheels
- Tyre worn close to the legal limit
- Tyre worn on the inner or outer edge
- Tyre cracking or perishing
- Tyre damaged: bulge, cut or lump
- Wheel bearing has play or is rough
Buying a used car?
General information about this type of MOT defect, not advice about a particular car. How serious it is depends on the car; have any car you're buying inspected by a qualified mechanic.