TPMS Warning Light On? What It Means and What To Do

The TPMS warning light — a small horseshoe shaped symbol with an exclamation mark — is one of the most commonly misunderstood dashboard warning lights on modern vehicles. Many drivers assume it simply means a tyre is flat or low on pressure. While that's sometimes the case, the reality is often more complex — and ignoring the TPMS warning light can affect both your safety and your tyres.

At National AutoTec, we provide professional TPMS sensor supply and programming across Melbourne. Here's everything you need to know about what the TPMS warning light means and how to get it resolved properly.

What Is TPMS?

TPMS stands for Tyre Pressure Monitoring System — a system that continuously monitors the air pressure in each of your vehicle's tyres and alerts the driver when pressure drops below a safe threshold.

TPMS has been mandatory on all new passenger vehicles sold in Australia since 2014 — which means the vast majority of modern vehicles on Melbourne roads are equipped with it.

There are two types of TPMS:

Direct TPMS A pressure sensor is mounted inside each wheel — typically attached to the valve stem. Each sensor continuously transmits tyre pressure data to a receiver module in the vehicle. This is the most common and most accurate type of TPMS.

Indirect TPMS Rather than using dedicated pressure sensors, indirect TPMS uses the vehicle's ABS wheel speed sensors to detect a tyre that is rotating faster than the others — indicating lower pressure and smaller diameter. No dedicated sensors are required.

Why Is My TPMS Warning Light On?

The TPMS warning light can illuminate for several different reasons:

Low Tyre Pressure The most common and straightforward cause — one or more tyres have dropped below the system's pressure threshold. Check all four tyres with a quality tyre pressure gauge and inflate to the correct pressures as specified in your vehicle's door jamb label or owner's manual. If the light extinguishes after inflating, the system is functioning correctly.

Faulty TPMS Sensor Direct TPMS sensors contain a battery that lasts approximately 5-10 years depending on the vehicle and operating conditions. When the sensor battery dies, the sensor can no longer transmit pressure data — triggering the TPMS warning light. A faulty sensor must be replaced.

TPMS Sensor Not Programmed After Tyre Change When tyres are changed — particularly if new sensors are fitted or sensors are rotated between positions — the TPMS system needs to be updated to recognise the new sensor positions and identities. Without a TPMS relearn procedure, the system doesn't know where each sensor is and the warning light persists.

TPMS Receiver or Module Fault The TPMS receiver module — which receives and processes signals from the wheel sensors — can develop faults. A faulty receiver will cause persistent TPMS warning lights regardless of tyre pressure or sensor condition.

Temperature Changes Tyre pressure changes with temperature — dropping approximately 1 PSI for every 6°C drop in ambient temperature. On cold Melbourne mornings, it's not uncommon for the TPMS light to illuminate if tyres were inflated at warmer temperatures. Inflating to correct pressures resolves this.

Aftermarket Wheels or Tyres If aftermarket wheels have been fitted without compatible TPMS sensors, or if the original sensors weren't transferred to new wheels, the TPMS system will trigger a warning light.

Why Does TPMS Sensor Replacement Require Programming?

Each direct TPMS sensor has a unique ID code that is programmed into the vehicle's TPMS receiver. When a sensor is replaced — whether due to battery failure, physical damage or valve stem damage — the new sensor's ID must be programmed into the receiver so the system can recognise and communicate with it.

Without correct programming, the vehicle doesn't know the new sensor exists — and the TPMS warning light will persist regardless of tyre pressure.

Programming a TPMS sensor requires specialist equipment that can both read the sensor's ID and program it into the vehicle's TPMS system — a procedure that goes beyond what most tyre shops are equipped to carry out.

At National AutoTec, we supply OEM and quality aftermarket TPMS sensors and program them to your vehicle's TPMS system — ensuring correct integration and elimination of the warning light. Please note that we supply and program sensors only — physical sensor fitting is carried out by your tyre shop.

OEM vs Aftermarket TPMS Sensors

When replacing a TPMS sensor, you have two options:

OEM TPMS Sensors Original equipment manufacturer sensors — identical to the sensor fitted at the factory. OEM sensors offer guaranteed compatibility and correct pressure reporting for your specific vehicle. They are typically more expensive than aftermarket options.

Aftermarket Universal TPMS Sensors Quality aftermarket universal sensors are programmable to work with a wide range of vehicle makes and models — offering a cost effective alternative to OEM sensors. A quality aftermarket sensor programmed correctly will function identically to the OEM sensor in normal use.

At National AutoTec, we supply both OEM and quality aftermarket sensors — recommending the most appropriate option for your vehicle and budget.

TPMS Programming at National AutoTec

Our TPMS service covers all major vehicle makes and models across Melbourne — with our mobile service attending your tyre shop, workshop or location for convenient on-site sensor programming.

Services include:

• OEM & aftermarket TPMS sensor supply & programming
• TPMS system diagnostic scanning
• TPMS warning light diagnosis & reset
• TPMS receiver & module diagnosis & replacement
• TPMS relearn procedures
• Fleet TPMS sensor supply & programming

Call us on 03 9969 3604 or book online today.