P2456: Particulate Filter Pressure Sensor A Circuit Intermittent/Erratic
What to do
Not dramatic, but each dropout skews the filter's fuel gauge — fix rather than tolerate.
What this code means
The filter pressure signal is cutting in and out — wiring living beside the exhaust, convicted the standard way, with each dropout corrupting the soot estimate a little. The bookkeeping consequence is why it should not be lived with: an estimate nudged wrong every drive eventually schedules the wrong regenerations.
Likely causes
Start here
- Intermittent wiring fault · moderate
- Corroded or loose connector · easy
Less common
- Exhaust heat damage to sensor harness · moderate
Symptoms
Components involved
Information, not instruction
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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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What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
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