TPMS Sensor Not Reading? Here’s Why
Troubleshooting • TPMS Sensors
TPMS Sensor Not Reading? Here’s Why
If your TPMS sensor is not reading, showing “no signal”, blank data, or a missing tyre, it usually means the sensor has lost communication, the battery is low, or the sensor needs to be re-paired.
This guide explains the most common reasons a tyre pressure monitoring system (TPMS) sensor stops reporting, how to fix it, and when replacement may be required.
Part of the Safety Sam knowledge hub: TPMS Knowledge Hub.
Quick Answer
A TPMS sensor usually stops reading because of:
- Low or flat sensor battery
- Sensor not paired correctly
- Signal range issues (common when towing)
- Sensor damage or water ingress
- Valve stem or fitting issue
- Receiver or app connection issue
1. Low Sensor Battery (Most Common Cause)
Many external TPMS sensors use small replaceable batteries. When battery voltage drops, the sensor may transmit inconsistently or stop reporting entirely.
Symptoms include:
- Intermittent readings
- “No signal” warnings
- Fault warnings after driving for a short time
Replace the battery and re-check readings before assuming the sensor is faulty.
2. Sensor Not Paired or Assigned Correctly
If you’ve rotated tyres, replaced a sensor, or reset the receiver, the system may not recognise the correct wheel position.
Re-enter pairing mode and assign the sensor to the correct tyre location.
Installation help: How to Install a TPMS
3. Signal Range Problems (Especially When Towing)
If the sensor that stops reading is on your caravan or trailer, signal range may be the issue.
Causes include:
- Distance between vehicle and van too great
- Metal structures blocking signal
- Weak sensor battery struggling at distance
For towing setups: Best TPMS for Caravans & Towing
4. Sensor Damage or Water Ingress
Sensors are exposed to road debris, weather, and vibration. Damage can occur from:
- Kerb strikes
- Corrosion
- Water entering the housing
- Overtightening onto valve stems
Inspect the sensor closely. If damaged, replacement may be required.
5. Valve Stem or Air Leak Issue
If the sensor is not sealed properly on the valve stem, you may lose both signal and pressure.
Ensure the sensor is firmly fitted (but not overtightened) and that the valve core is intact.
6. Receiver or App Connection Problem
Sometimes the issue is not the sensor but the receiver or smartphone connection.
- Restart the receiver or app
- Check Bluetooth connection (if applicable)
- Ensure firmware or app version is current
What to Do When a TPMS Sensor Stops Reading
- Confirm tyre pressure manually with a gauge.
- Identify which sensor is not reporting.
- Replace the sensor battery (if external).
- Inspect for visible damage.
- Re-pair or reset the sensor.
- Test by driving for several minutes.
If the problem only happens at highway speeds: Why Does My TPMS Go Off on the Highway?
When Should You Replace a TPMS Sensor?
Replace the sensor if:
- Battery replacement does not restore signal
- The housing is cracked or corroded
- It repeatedly drops signal despite correct setup
View a reliable external system here: Tyre Pressure Monitoring System
FAQs
Why is only one TPMS sensor not reading?
Most often due to low battery, sensor damage, or pairing issues specific to that wheel.
Can a dead battery cause a TPMS sensor to stop reading?
Yes. A flat battery is one of the most common reasons for “no signal” warnings.
Do I need to replace the whole TPMS if one sensor fails?
No. Individual sensors can usually be replaced without replacing the entire system.
