OBD-II trouble code
P0228: Throttle/Pedal Position Sensor/Switch "C" Circuit High
SAE J2012 APR2002: throttle/pedal position sensor/switch C circuit high. High is measured with the circuit connected. An open and a short to power can share that reading. The printed pair is a separate throttle-position sensor.
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 P0228 mean?
SAE J2012 APR2002 names P0228 Throttle/Pedal Position Sensor/Switch "C" Circuit High. Circuit high is measured with the circuit connected. The manufacturer sets the level. Section 6's stuck-near-5-volts example is sensor A, which may be stored as the general code or as the high code. Five volts is that example, not a P0228 limit.
On the 2007 G6, sensor 2 open and sensor 2 shorted to voltage both read 5 volts and both set the high code, P0223. The unplugged sensor is expected to sit above 4.8 volts, so a high unplugged reading is not itself the short. The jumper to the low reference is what fails if the wire is open or shorted to voltage. That entire arrangement is sensor 2. The G6 procedure does not define sensor C. Track C may be biased the same way or the opposite way. Use the disconnected-circuit voltage this chart prints. If a high reading with the sensor unplugged matches that published bias, you have not proved a short to power.
Prove a short to power like this: ignition off, unplug the sensor, disconnect the module, then ignition on. The signal wire should not be at battery voltage, and it should not be above the disconnected voltage the chart allows. Prove an open separately: continuity, both ends disconnected, ignition off. Stopping after the unplugged high reading skips one of those two faults. A low-reference open can also lift a track. Measure the return before the sensor is condemned. The G6 table does that for sensor 2 by setting P0223 when the low reference is open. Whether track C does the same is this chart's fault table, not an assumption.
RepairPal's throttle-position sensor replacement, updated 3 September 2026, averages $185–$258, labor $78–$114 and parts $107–$145. The sensor that page describes sits opposite the throttle-cable spring, and that separate sensor is the printed pair, rounded, where the diagram puts track C there. Where the sensor is integrated in the throttle body, RepairPal's throttle-body average of $623–$766 is the other job and is not this range. Wiring is outside both. Do not move a motor-driven plate by hand with the ignition on.
Common causes
- Track C above the high limit this chart prints, circuit connected
- The signal wire shorted to voltage, module disconnected, above the chart's disconnected-circuit voltage
- The signal wire open, continuity failed with both ends disconnected, which can leave a pull-up looking like a short
- A return that is open, if this fault table lifts the track when the low reference breaks
- A G6 sensor 2 jumper test, terminals F and C, used on a connector that is not that throttle body
- A part replaced because the unplugged pin sat at the bias the chart already expected
Symptoms
- P0228 stored
- Track C above the published high limit with the sensor connected
- An unplugged reading that matches the chart's bias, which is not yet a short
- An unplugged reading that stays high after the module is disconnected and above the allowed bias, which is the short to voltage
- No 4.59-volt or 4.8-volt G6 number, unless this chart is that G6 page, which does not list P0228
Diagnostic steps
- 1.Confirm track C exists. Park. Stop if the pedal does not move rpm.
- 2.Key on, sensor connected, compare track C with the high limit this chart prints. Do not use 4.59 volts from G6 sensor 2.
- 3.Key off, unplug the sensor. If the signal pin matches the disconnected voltage in this chart, record that as the bias, not as a failed short test.
- 4.Disconnect the module. Key on. A signal pin at battery voltage, or above the allowed bias, is a short to voltage. Continuity with both ends off and the ignition off is the open. Do both.
- 5.Check the low reference for an open before the sensor is replaced. A lifted return can set a high code on inputs built like the G6 sensor 2. Confirm the pattern on this chart rather than importing it.
- 6.Do not install the G6 fused jumper on terminals F and C unless this connector is that G6 throttle body and the code is the one that procedure names.
- 7.Where track C is a separate sensor, that job is the printed pair. Where it is built into the throttle body, the body figure in the notes is the job. Wiring is outside both. Do not lever a motor-driven plate.
- 8.Verify track C stays under the published high 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. That estimate is the sensor opposite the throttle-cable spring. Where the sensor is integrated in the body, throttle body replacement averages $623–$766 and is outside this pair. A signal wire is not in 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.