By iCarsoft Official Store Technical Team, Automotive Diagnostics Editors · Updated September 5, 2026 · OEM technical references checked
Quick Answer
The P0228 code means throttle/pedal position sensor/switch c circuit high. It does not prove the pedal or throttle assembly is defective, C is a universal third sensor, or high means the throttle plate is physically open. Save the scan, identify the exact architecture, and test the physical and electrical paths before selecting a repair.
What Does the P0228 Code Mean?
P0228 is standardized as Throttle/Pedal Position Sensor/Switch C Circuit High. It names a monitored result, not a guaranteed failed part. The reporting module, suffix and companion faults determine the relevant test branch.
Electronic throttles use redundant pedal and throttle channels with manufacturer-specific labels and scaling. P0228 is the high electrical classification for Sensor/Switch C. Signal shorts, lost sensor ground, connector faults or shared reference interactions can create it.
Read each suffix as its exact monitor classification, not a universal physical direction. Confirm the designation, units, signal source and test state before comparing scan data with an external measurement.
GM bulletin 21-NA-149 lists P0228 among possible DTCs caused by engine-harness chafing on specifically covered vehicles. It illustrates the need to inspect shared harness routing, but does not establish that location or repair for another VIN.
Separate P0228 from adjacent fault families
| Code | General description | Key distinction |
|---|---|---|
| P0228 | Throttle/pedal position sensor/switch C circuit high | High electrical classification for OEM-defined channel C. |
| P0227 | Throttle/pedal position sensor/switch C circuit low | Low classification for the same channel family. |
| P0226 | Throttle/pedal position sensor/switch C range/performance | Plausibility or performance classification. |
| P0223 | Throttle/pedal position sensor/switch B circuit high | High branch for B, not the P0228 C channel. |
Record the complete P0228 description. The suffix, reporting module and companion faults can change the diagnostic path. Current manufacturer evidence governs when the queue wording conflicts.
P0228 Symptoms and Likely Causes
P0228 symptoms depend on fault status and the fallback strategy. Record what the driver and modules reported. A symptom list is not a parts list.
Move out of traffic and save every throttle and pedal fault.
Do not continue a road test with unpredictable response.
Compare all redundant channels before deciding where the fault lies.
Inspect connectors, water entry and harness rub points.
Practical cause-checking order
- Accessible connection: Loose, wet, corroded or spread pedal, throttle-body or intermediate connector terminals.
- Circuit or shared path: Signal short to reference or power, sensor-ground open or high resistance, or harness chafing.
- Supporting system: Shared reference or ground disturbance affecting several sensor channels together.
- Named component: Pedal or throttle position assembly that fails the specified channel and correlation tests.
- Controller or software: Throttle controller, PCM calibration or input fault after every external channel passes.
Did P0228 appear after recent pedal, throttle-body, intake, engine, battery, controller, connector or harness work? Recheck disturbed connectors, grounds, hoses, fluids, part numbers and setup steps for the throttle or pedal position sensor C high-signal path. Record battery and software history; a post-repair code does not prove the new part is defective.
How Serious Is P0228, and Can You Drive?
Arrange diagnosis promptly. When the warning is steady, operation remains normal and the owner's manual permits it, a short light-load trip to a repair facility may be reasonable. Avoid demanding use until the throttle or pedal position sensor C high-signal path is understood. P0228 does not provide a universally safe distance.
Record event conditions and recent service. Never reproduce unsafe acceleration.
Stop and arrange a tow if acceleration is unintended or unpredictable, reduced power makes traffic unsafe, the engine races or stalls, the throttle moves unexpectedly, the MIL flashes, or safe vehicle control is lost. Pause circuit testing if the reference circuit cannot be isolated safely.
Electronic throttles can move without hand contact and some vehicles use shared sensor references. Keep fingers and tools out of the bore, key off and depower as directed, and never apply battery power or ground directly to a controller pin.
How to Diagnose P0228 in the Right Order
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Save the complete fault record
Scan before clearing. Save P0228 wording, suffix, reporting module, status, freeze frame, companion codes, supply voltage and available data for the throttle or pedal position sensor C high-signal path. Record failure order, recent repairs and restart behavior for later comparison.
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Identify the VIN-specific monitor and architecture
Use the VIN, engine, transmission and equipment codes to obtain the current wiring diagram, connector views, monitor description and bulletins. Electronic throttles use redundant pedal and throttle channels with manufacturer-specific labels and scaling. P0228 is the high electrical classification for Sensor/Switch C. Signal shorts, lost sensor ground, connector faults or shared reference interactions can create it. Confirm software identifiers and service-action eligibility directly; a bulletin for one application does not establish coverage for another.
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Inspect the accessible physical path
Follow the safety procedure, then inspect connectors, locks, seals, terminals, clips and harness routing for the throttle or pedal position sensor C high-signal path. Look for heat, abrasion, fluid entry, corrosion, tension and unsuitable prior repairs. Check the supporting mechanical, air, exhaust, fluid or vacuum path named in the service information. Photograph evidence before correcting it.
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Prove circuits and physical conditions
Use the high-impedance meter, manufacturer-approved breakout leads, suitable oscilloscope and safe electronic-throttle service equipment as the exact procedure requires. Prove feeds, grounds and references under the specified load, then test signal or control integrity at the correct states. Isolate components before resistance tests. Never bridge a controller pin to battery or ground, and do not substitute a continuity beep for a load, pressure or waveform test.
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Compare supported command and response
Graph every supported pedal and throttle channel together from rest through a slow controlled sweep with the engine state specified by the manufacturer. Compare direction, continuity and correlation; do not force the throttle plate or infer integrity from one PID. Compare scan evidence with the external measurement and companion faults. A command does not prove physical movement, pressure, current, temperature or torque. A missing PID or active test is a coverage limitation, not evidence that the vehicle component failed. Stop any test if operation becomes unsafe.
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Choose the supported repair and setup
Repair the failed path and correct the reason for damage. Confirm part application, required setup authorization and any relearn. Consider a controller only after its powers, grounds, inputs, outputs and service information pass.
Specifications are vehicle-specific. There is no universal voltage, resistance, current, pressure, waveform, timing, temperature, percentage, learned value or drive cycle for P0228. Test state, connector location and system design change what a valid value means. Use only specifications for the exact VIN and do not transfer the OEM example in this article to another application.
P0228 Repairs and Typical Costs
The correct P0228 repair follows the failed test. Wiring, a physical repair, a proven component, software and controller work are different outcomes. Do not replace an assembly from the generic code alone.
After installation, recheck connector seating, harness clearance, fluid or mechanical setup and every required learn. If an OEM bulletin appears relevant, document vehicle eligibility, installed calibration and prescribed action. The existence of the bulletin in the references does not promise warranty, free repair or a software cure for other vehicles.
| Possible path | Current US estimate |
|---|---|
| Restore Sensor C connector, reference, signal, ground or chafed harness | VIN-specific quote |
| Correct a proven shared reference, ground or intake installation problem | VIN-specific quote |
| Replace the mapped pedal or throttle assembly only after its channel test fails | VIN-specific quote |
| Complete the required throttle or pedal relearn and apply software only when specified | VIN-specific quote |
There is no single national P0228 repair price because these rows are alternative outcomes. Ask for an itemized estimate showing diagnostic time, parts, labor, fluids, service-information access and verification. Location, taxes, related damage and warranty eligibility change the total. Do not add the rows together or authorize an assembly without the supporting failed test.
Using iCarsoft CR Pro S for P0228
On a supported vehicle, iCarsoft CR Pro S can retrieve accessible module faults, save available freeze frame, display ECU-provided live data and create a diagnostic report. For P0228, preserve the original evidence and compare related modules before clearing an erasable record.
Preserve the throttle or pedal position sensor C high-signal path evidence
iCarsoft CR Pro S
Review supported codes and relevant live data together. Confirm the exact VIN, controller access, PIDs and any requested active test with iCarsoft before purchase; generic product capabilities do not guarantee a P0228-specific function.
Check current CR Pro S price and availabilityCheck CR Pro S compatibility by VINThe official product page describes full-system diagnosis, available freeze frame/live data, reports and supported active tests; every function remains vehicle, ECU and software dependent. Supported topology and coding availability varies by vehicle and ECU and requires VIN confirmation. Follow OEM prerequisites and stop for abnormal operation.
Know the measurement boundary. The scanner reports information supplied by the vehicle. It does not directly prove terminal tension, circuit load capacity, leakage, pressure, temperature, mechanical travel or internal condition in the throttle or pedal position sensor C high-signal path. It also cannot replace the high-impedance meter, manufacturer-approved breakout leads, suitable oscilloscope and safe electronic-throttle service equipment when the OEM procedure requires them. Interpret commanded and reported values alongside measured evidence.
Verify the P0228 Repair
After repair, verify connectors, harness clearance, setup and controller supply. Save post-repair findings, then clear only erasable records through the approved procedure. Battery disconnection is not a repair.
Run the manufacturer's applicable verification conditions in a safe workshop or route. Compare the original operating state with current data for the throttle or pedal position sensor C high-signal path, and check current and pending faults in related modules. One clean start or idle does not prove every conditional monitor completed.
If P0228 returns, compare its suffix, status, failure order and operating conditions with the saved baseline before replacing another part. Revisit the failed branch and inspect anything disturbed. Keep mechanical repair, monitor completion, readiness and local inspection eligibility as separate outcomes.
A permanent P0228 can remain immediately after a successful repair. If the vehicle stores it as a permanent DTC, a scan tool or battery disconnect cannot erase it. Once current and pending faults are absent, the OBD system removes the permanent record only after the applicable monitor reruns and passes.
Related Throttle Or Pedal Position Sensor C High-Signal Path Code Guides
P0228 Frequently Asked Questions
Does P0228 mean the named component is bad?
No. P0228 describes throttle/pedal position sensor/switch c circuit high, not a confirmed part. It also does not prove the pedal or throttle assembly is defective, C is a universal third sensor, or high means the throttle plate is physically open. Test accessible wiring, supplies, grounds and supporting physical conditions, then follow the exact monitor tree. Replace a component only when its branch fails or an applicable OEM action specifically supports it.
What should I check first for P0228?
Save every module's codes and freeze frame before clearing. Confirm the full definition, suffix and VIN architecture. Then inspect recent pedal, throttle-body, intake, engine, battery, controller, connector or harness work, connectors and shared supplies. Those facts determine whether the next test needs the high-impedance meter, manufacturer-approved breakout leads, suitable oscilloscope and safe electronic-throttle service equipment or a manufacturer-specific functional procedure.
Can I drive with the P0228 code?
Only consider a short light-load trip when operation is normal and the owner's manual permits it. Stop if acceleration is unintended or unpredictable, reduced power makes traffic unsafe, the engine races or stalls, the throttle moves unexpectedly, the MIL flashes, or safe vehicle control is lost. Pause circuit testing if the reference circuit cannot be isolated safely. The code number cannot establish a safe mileage allowance, and another warning can make the situation more urgent.
Why did P0228 return after a part was replaced?
The original circuit or supporting-system fault may remain, the part or setup may be wrong, or the first diagnosis may have confused a monitored result with a failed component. Compare the new failure conditions with the saved record and recheck every disturbed connection before buying another part.
How much does a P0228 repair cost?
A VIN-specific estimate is required because diagnosis may lead to wiring, a supporting physical repair, a verified component, software or a controller. Ask which failed test supports the quote and whether diagnosis, taxes, setup and post-repair verification are included.
Can CR Pro S diagnose and clear P0228?
On a supported vehicle, CR Pro S can organize available faults, freeze frame, live data and reports, and can clear erasable records after repair. Confirm exact ECU coverage. It cannot force-clear a permanent DTC or replace physical measurements for the throttle or pedal position sensor C high-signal path.
The iCarsoft Official Store Technical Team maintains the store's fault-code library. This guide organizes published manufacturer evidence and verified product information; it does not document a hands-on test of a particular vehicle or claim an individual engineer's review.
Technical and cost references
- GM Service Bulletin 21-NA-149 — Engine Wire Harness Chafing and Various DTCs. Lists P0228 among application-specific faults associated with a covered engine-harness chafing condition.
- SAE J2012 Recommended Practice, March 1999 USPTO exhibit. Lists P0228 Sensor/Switch C Circuit High Input and separates the neighboring C-channel classifications.
- California Bureau of Automotive Repair — On-Board Diagnostic Test Reference. Permanent DTCs are removed by the vehicle after applicable verification, not by a scan-tool erase command.
Product information: Official iCarsoft CR Pro S page.
Editorial note: General diagnostic education, not a substitute for the owner's manual, current VIN-specific service information or professional inspection. Test limits, procedures, coverage and costs vary. Related articles provide context; apply only the specifications and repair procedures that match the vehicle. No universal failure rate, repair price or outcome is implied.
