P0229
Throttle/Petal Position Sensor/Switch C Circuit High Input
Powertrain Speed/Idle Control Throttle Position Sensor 🟡 Moderate — Fix within a week
💬
What This Actually Means
In plain language — no jargon

The engine computer detected that the throttle position sensor C is sending a voltage signal that's too high, like a stuck gas pedal reading. This tells the ECU the throttle is wide open when it shouldn't be, causing the engine to run poorly or not respond correctly to your pedal input.

⚡
Symptoms You May Notice
3 known symptoms for this code
Check Engine Light illuminated
Engine hesitation or lack of power response
Rough idle or stalling
🔬
Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors voltage from the throttle position sensor C circuit, expecting a signal between 0.5V and 4.5V that correlates with pedal position. When the voltage exceeds the maximum threshold (typically >4.8V), the ECU logs a high-input fault because it indicates a wiring short, sensor failure, or internal ECU issue.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
TPS C Voltage 0.5V to 4.5V >4.8V (High Input)
Signal Consistency Smooth ramp with pedal movement Erratic or stuck-high reading
🔧
Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Wiring harness connector TPS C
Inspect and reseat the sensor connector at the throttle body; corrosion or a loose pin causes high voltage signals.
2
Throttle Position Sensor C
Replace the faulty sensor if voltage remains high after connector inspection.
3
ECU or PCM
Have a dealer test the ECU output circuits if sensor and wiring are confirmed good; internal failure is rare but possible.