P0452: Evaporative Emission System Pressure Sensor/Switch A Circuit Low
What to do
Driveable with no symptom beyond the warning light.
What this code means
The fuel tank pressure sensor signal has fallen below its plausible range, which usually means a short to ground or a lost reference voltage rather than a genuine tank vacuum. Checking for five volts of reference at the connector separates a failed sensor from a harness fault immediately.
Likely causes
Start here
- Faulty fuel tank pressure sensor · moderate
- Signal wire shorted to ground · moderate
- Corroded or loose connector · easy
Less common
- Failed sensor reference voltage supply · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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