The U-shaped light with an exclamation point. For those curious, it’s our TPMS warning light. TPMS is short for tyre pressure monitoring system (TPMS). It’s an indicator to the driver that one of more tyres on the vehicle are improperly inflated, whatever the reason.

In the past, studies and other analysis demonstrated a significant number of road accidents were caused by tyre-related events. Many of these have been down to underinflated tyres that have caused difficulties while driving, while some have resulted in tyre blowouts requiring action from the deriver that endangers lives of the driver, other drivers, passengers, and pedestrians.

As a consequence, these studies have led to decisions in the European Parliament in the EU in 2014 and at Congress in the United States in the early 2000s to make TPMS compulsory on all new vehicles. What followed, was a significant reduction in accidents relating to tyres as the cause.

What Should I Do When My TPMS Light Comes On?

First, don’t panic. When it’s safe to do so, stop and park your care.

After this, check your tyres manually with a tyre pressure gauge. If you don’t have one, you can drive to the nearest petrol station or garage to try and buy one – if you’re lucky, they may even let you borrow one.

If your tyres have low pressure readings, inflate them to within the manufacturer’s recommended levels. Assuming your TPMS system is working correctly, inflating your tyres may be enough to have the TPMS light turn stop illuminating.

But there can be times when it doesn’t. TPMS is a helpful tool, but sometimes it can have a fault and a TPMS system doesn’t tell us too well what exactly the fault is. Sometimes your tyres can have the correct pressure, yet the TPMS light comes on even if the tyres aren’t overinflated or underinflated.

How to Deal with a TPMS Light Malfunction

There are a few possible reasons why a TPMS light may malfunction on a vehicle.

One: Tyres Have Been Recently Replaced

When tyres have been replaced, a TPMS relearn or reset needs to be performed. Due to the technical nature of the TPMS programming tools, this should be done by a service centre professional.

For more on this, please see our post on TPMS Relearn Procedures.

Two: A TPMS Sensor Battery May Be Dead

You TPMS battery could be dead. Batteries can’t be replaced as they’re usually held in place by resin with soldered connections. However, TPMS batteries can last from five to ten years, depending on how the vehicle is used.

And as we’ve explained in a recent post, when you replace one sensor, it’s usually wise to replace each sensor on each tyre. This is because when one sensor battery has died, it’s a safe bet the other sensors will too as they’re exposed to the same environment as the broken sensor.

Three: A TPMS Sensor May Be Damaged

Like reason number two, some sensors just get worn out though are hard-wearing. And again, it’s wise to replace all four at once.

Keep in mind, however, you will need to perform relearn procedures on any new TPMS sensors. In pragmatic terms, this is best done by your mechanic or service centre as TPMS sensors need to be programmed using TPMS programming tools whose cost makes them fairly inaccessible to the average motorist.