OBD-II trouble code
P0227: Throttle/Pedal Position Sensor/Switch "C" Circuit Low
SAE J2012 APR2002: throttle/pedal position sensor/switch C circuit low. Low is measured with the circuit connected. The G6 rule that an open sensor 2 signal reads high does not transfer to sensor C. The printed pair is a separate throttle-position sensor. The reference is read with the module connected.
Quick facts
- System
- Powertrain
- Category
- Throttle / Idle
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $190 – $260 (separate throttle-position sensor replacement, parts and labor, RepairPal national average updated 3 September 2026, where sensor C is the sensor opposite the throttle-cable spring; a throttle body with that sensor built in, and wiring, are outside this pair)
- DIY difficulty
- Shop recommended
Browse every code in P0200–P0299, or start from the full code library.
What does P0227 mean?
SAE J2012 APR2002 names P0227 Throttle/Pedal Position Sensor/Switch "C" Circuit Low. Circuit low is measured with the external circuit, component, or system connected. The voltage, or other signal, that counts as low is specified by the manufacturer. Section 6's near-0-volt example is sensor A and may be stored as the general code or as the low code. It is not a P0227 threshold.
The 2007 G6 table says a short to ground on sensor 2's signal reads 0 volts and sets P0222, while an open on that signal reads 5 volts and sets P0223. That split is sensor 2 on that vehicle. Sensor C is a different SAE row, and the G6 procedure does not define it. An open on track C might pull the pin low, or it might release the pin to a pull-up, depending on how this input is biased. The disconnected-voltage line in this chart is the authority. Guessing from sensor 2 will condemn the wrong fault.
With track C connected, compare the scan value with the low limit this chart prints. Then switch the ignition off, unplug the sensor, and disconnect the module. If the signal wire to ground has continuity, the wire is shorted to ground and the sensor was not required for the short. That continuity check is unpowered. The module stays disconnected for unpowered resistance checks and is reconnected before any powered reference reading. If that wire is clear and the connected reading was low, the sensor is what pulled it down, provided the reference is actually present. A reference that has collapsed also pulls a track low. Measure the reference with the module connected and the sensor unplugged, key on, pin to ground, against the published reference. A module-generated reference cannot reach the connector while the module is unplugged, so that powered check is not done with the module disconnected. An open signal wire is a third measurement: continuity with both ends disconnected, ignition off. Do not skip it because the low code 'sounds like' a short.
RepairPal's separate throttle-position sensor, updated 3 September 2026, averages $185–$258, labor $78–$114 and parts $107–$145, for the sensor opposite the throttle-cable spring. The printed pair is that job, rounded, where the diagram puts track C in that separate sensor. Where the sensor is integrated in the throttle body, RepairPal's throttle-body average is $623–$766 and is named with the cost, not printed as this range. Wiring is outside both. Do not move a motor-driven plate by hand with the ignition on.
Common causes
- Track C below the low limit this chart prints, measured with the circuit connected
- The signal wire shorted to ground, found with the sensor unplugged and the module disconnected
- A reference that is not at the published voltage, measured with the module connected and the sensor unplugged, which can pull the track down without a signal-wire short
- An open signal wire, which has to be tested even though the code says low, because the bias direction is this chart's
- The G6 sensor 2 open-reads-5-volts result applied to sensor C
- A part replaced while the unplugged wire still shows the short
Symptoms
- P0227 stored
- Track C at or under the low limit in this service information, key on, sensor connected
- The low reading gone with the sensor unplugged, and the wire clear of ground, which points at the sensor
- The low reading still there with the sensor unplugged, which points at the wire or the reference
- No 0.25-volt G6 figure, because that limit is sensor 2
Diagnostic steps
- 1.Confirm a C track exists. Park. If the pedal does not change rpm, stop.
- 2.Key on, sensor connected, compare track C with the low limit this chart prints. Do not use 0.25 volt from the G6 sensor 2 test.
- 3.Key off, unplug the sensor, disconnect the module. Signal wire to ground: continuity means a short to ground. This resistance check is why the module is disconnected. No continuity means the sensor, still connected a moment ago, was the path to ground, once the reference has been measured with the module back on.
- 4.Reconnect the module. Key on, sensor still unplugged: measure the reference pin to ground against the published reference. A missing reference is not a signal short. Do not leave the module disconnected for this reading.
- 5.Signal-wire continuity, both ends off, ignition off, is the open test. Finish it. The word low does not retire it. The module is disconnected for that unpowered check only.
- 6.Do not call a pull-up voltage a short to power during this low-code test. Short to power is the high code's question.
- 7.The part comes after the wire and the reference pass. The printed pair is the separate sensor. A track built into the throttle body uses the body figure in the notes. Wiring is outside both. Do not lever a motor-driven plate.
- 8.Verify track C stays above the published low limit through a pedal sweep in park.
Repair cost
$190 – $260 (separate throttle-position sensor replacement, parts and labor, RepairPal national average updated 3 September 2026, where sensor C is the sensor opposite the throttle-cable spring; a throttle body with that sensor built in, and wiring, are outside this pair)
RepairPal's throttle position sensor replacement, updated 3 September 2026, averages $185–$258 (labor $78–$114, parts $107–$145), rounded to $190–$260. The sensor on that page sits opposite the throttle-cable spring, so the pair is the separate sensor. Where the sensor is integrated in the throttle body, throttle body replacement averages $623–$766 on the same date and is outside this pair. A shorted signal wire is not either part. Wiring is outside the pair. Check-engine diagnosis is $125–$183 and is separate.
Estimate your repair
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Open the Repair Cost Estimator with check engine light diagnosis preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
Leave this one to a qualified shop. The barrier here is manufacturer-grade tooling, training, or certification that most home setups do not have. DIY attempts often produce a more expensive problem than the original code.