Pedal Position Sensor C Circuit Intermittent
The gas pedal sensor (the one that tells the engine how hard you're pressing) is sending spotty, unreliable signals to the computer. It's like a light switch that keeps flickering on and off instead of working smoothly.
The ECU monitors the Pedal Position Sensor C (typically redundant sensor for safety) for consistent voltage signals between 0-5V that correlate with pedal movement. An intermittent fault occurs when the signal drops out briefly or shows erratic voltage spikes that don't match pedal input, triggering a rationality check failure.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor Voltage | 0.5V to 4.5V (smooth, linear sweep) | Intermittent dropouts, noise spikes, or signal loss >50ms |
| Signal Rationality Check | Sensor C matches Sensor A/B within tolerance | Mismatch between redundant sensors or erratic transitions |
Code P1222 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P1222 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.