P2410 indicates the powertrain control module has detected a lower-than-expected voltage signal from the fuel cap sensor or switch circuit. This sensor informs the EVAP system whether the fuel cap is present and properly tightened. A 'low' reading usually means the circuit is shorted to ground, the sensor is failing, or the cap is not making proper contact.
The sensor that detects cap presence or tightness can fail internally, stick, or give a constant low-voltage signal. This is the single most common cause of P2410.
A worn, damaged, or loose cap may not engage the sensor properly, or a cap without the correct seal/tether can cause the switch to read low.
A short to ground, pinched wire, corrosion, or poor connection between the fuel cap sensor and the PCM can pull the signal voltage low.
Physical damage, rust, or misalignment of the filler neck can prevent the cap from seating fully and the sensor from closing correctly.
A rare cause; the PCM could misread a good sensor signal due to an internal input problem. This should only be considered after the cap, sensor, wiring, and grounds have been verified.
The definition is universal; the diagnostics are engine-specific. Open your vehicle for the codes documented for it:
Usually yes. It typically does not affect engine performance or safety, but it will illuminate the check engine light and can cause an emissions inspection failure.
Not always. A loose cap can set EVAP leak codes, but P2410 specifically points to the cap sensor or switch circuit reading low, so the sensor, wiring, or cap engagement is more likely the issue.
Almost never. PCM failure is an uncommon cause of this code. Replace or repair the fuel cap, sensor, and wiring first, and only suspect the PCM after everything else is ruled out.
It generally does not reduce fuel economy, but if it accompanies an actual EVAP leak, fuel vapors may escape into the atmosphere rather than being recovered by the system.