What it means
The fuel tank pressure sensor signal is above the expected maximum voltage, typical of a short to supply or a sensor that has failed high.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The fuel-tank pressure sensor reports EVAP pressure changes to the control module through its signal circuit. P0453 sets when that signal is above the expected range, often because the signal wire is shorted to voltage, the ground circuit is open, or the sensor has failed high.
Common causes
Most likely first.
- Fuel tank pressure sensor failure
- Signal wire shorted to voltage
- Open or damaged ground circuit
- Corroded or loose connector
Symptoms
- Check engine light on
- Possible smell of fuel near tank or engine bay
- Failed emissions inspection
- Loose-cap warning may appear
How to diagnose it
- Review freeze-frame and live pressure-sensor data to confirm the high reading and the conditions under which it appeared.
- Inspect the tank-pressure sensor connector and harness for corrosion, loose pins, damaged insulation, or contact with a powered wire.
- Check the sensor ground and reference circuits against the manufacturer's wiring diagram and specifications.
- With the circuit isolated as directed by the manufacturer, test the signal wire for a short to voltage and check for an open or poor ground.
- If wiring and connections pass, test the tank-pressure sensor for an output stuck high before considering a module fault.
Common fixes
- Repair a signal wire shorted to voltage or a damaged harness.
- Restore a poor or open sensor ground and repair corroded connector terminals.
- Replace the tank-pressure sensor if it fails the manufacturer's test.
- Repair the control module only if the sensor and its circuits test correctly.
Can I keep driving?
You can usually continue driving if the vehicle behaves normally, but EVAP monitoring may be disabled and an emissions test may fail. Stop and investigate promptly if there is a strong fuel smell or a visible leak.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.