Throttle/Pedal Position Sensor C Circuit Intermittent
Code P0229 indicates an intermittent fault in the throttle/pedal position sensor 'C' circuit. This sensor is part of the electronic throttle control system and provides input to the PCM about accelerator pedal position. An intermittent signal can cause erratic throttle response, hesitation, or sudden loss of power. The issue may stem from a loose connection, damaged wiring, or a failing sensor.
1. Most Common Causes
- Intermittent short or open circuit in the throttle position sensor wiring
- Loose, corroded, or intermittent electrical connections in the sensor harness
- Faulty throttle position sensor (TPS) or accelerator pedal position (APP) sensor
- Intermittent loss of reference voltage (VREF) or ground to the sensor
- Engine control module (ECU) internal failure (rare)
2. Symptoms You Will Notice
- Check Engine Light on
- Intermittent hesitation or surging during acceleration
- Reduced engine power or limp mode
- Unresponsive or jerky throttle pedal
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data to capture conditions when fault occurred.
Step 2: Visually inspect wiring and connectors for damage, corrosion, or loose pins; repair as needed.
Step 3: Test sensor C voltage and resistance per manufacturer specs while wiggling harness to reproduce intermittent fault.
Step 4: If sensor is faulty, replace it and clear codes; test drive to confirm repair.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended as intermittent throttle response can lead to unsafe driving conditions. The vehicle may enter limp mode, limiting speed and acceleration.
How much does it cost to fix?▼
Typical repair costs range from $50 to $150 for a DIY sensor replacement, or $100 to $300 at a shop including labor and diagnostics.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.