Throttle/Petal Position Sensor/Switch C Circuit Range/Performance Problem
The engine computer detected that throttle position sensor C is sending signals outside its normal operating range, like a volume knob stuck between positions. This prevents the engine from properly controlling fuel and air mixture based on how far the accelerator pedal is pressed.
The ECM monitors voltage output from throttle position sensor C to verify pedal position accuracy. It compares the signal against expected ranges and cross-references with other throttle sensors for consistency. If voltage stays outside normal thresholds or shows erratic fluctuations, the fault triggers.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor C Voltage | 0.5V to 4.5V (linear progression with pedal) | Below 0.5V or above 4.5V, or erratic jumping |
| Sensor Cross-Check | C matches A/B sensors within 10% | Deviation exceeds 10% or signals conflict |
Code P0227 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, P0227 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.