P2299 – Brake Pedal Position / Accelerator Pedal Position Incompatible

Meaning of Code P2299

Code P2299 indicates a signal conflict between the Accelerator Pedal Position Sensor (APPS) and the Brake Pedal Position Sensor. The PCM (Powertrain Control Module) detects that the accelerator remains partially open while the brake is applied, which is considered a hazardous situation (e.g., risk of engine runaway).

• Normal Operation:
  When the brake is pressed, the PCM automatically reduces throttle opening to prevent engine overload.

• Code Triggering:
  If the PCM detects a fixed or inconsistent position of the accelerator during braking, it activates limp mode (reduced power) and logs P2299.

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Possible Causes

1. Faulty APPS: Internal resistance out of specification.

2. Failed Brake Pedal Position Sensor: Incorrect signal sent to the PCM.

3. Wiring Issues:

   • Short circuit or open circuit in the APPS or brake harness.

   • Oxidized connectors, bent pins, or damaged wires.

4. PCM Failure (rare).

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Common Symptoms

• 🚨 Check Engine Light On.

• 🐌 Reduced Engine Power (Limp Home mode).

• 🛑 Unstable Idle or stalling.

• 🚗 Unresponsive Acceleration despite pressing the pedal.

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Step-by-Step Diagnostic Procedure

1. Visual Inspection

• Locate the Sensors:

  • APPS: Usually near the accelerator pedal.

  • Brake Sensor: Under the dashboard, near the brake pedal.

• Check Connectors:

  • Disconnect and inspect pins for corrosion, oxidation, or damage.

  • Clean with contact spray (e.g., CRC Electrical Cleaner).

2. APPS Sensor Test

• Resistance Measurement:

  • Disconnect the APPS connector.

  • Using a multimeter in ohmmeter mode (Ω), measure the resistance between the sensor terminals.

  • Expected Values: Varies by model (e.g., 1,500–3,000 Ω with pedal released).

  • If out of range → Replace APPS.

• Voltage Test:

  • Reconnect the connector, turn ignition on (without starting).

  • Measure voltage between the signal terminal and ground.

  • Voltage should gradually vary from 0.5 V to 4.5 V when pressing the pedal.

3. Brake Pedal Sensor Test

• Use a Diagnostic Tool:

  • Read the live data from the brake sensor (should change from Released to Applied).

• Manual Test:

  • Disconnect the connector and check continuity between terminals when pressing the pedal.

4. Electrical Circuit Check

• Inspect APPS/Brake Harness:

  • Look for cut, pinched wires, or short circuits to ground.

  • Use a multimeter in continuity mode to check each wire between the sensor and PCM.

5. PCM Update

• Check TSBs (Technical Service Bulletins) for vehicle-specific software updates.

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Repair Solutions

1. Replace APPS or Brake Sensor if faulty (prefer OEM parts).

2. Repair Harness:

   • Waterproof soldering + heat shrink tubing for damaged wires.

3. Clean Connectors: Use contact spray and an anti-static brush.

4. Reset PCM:

   • Clear P2299 code with an OBD-II tool.

   • Perform an APPS learning procedure if needed (follow service manual).

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Specific Cases by Brand

• Volkswagen/Audi: Recurrent APPS connector corrosion issues under pedals.

• Toyota/Lexus: Brake sensor failures related to moisture (check sealing).

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Important Tips

• ⚠️ Safety: Always test the vehicle in a safe environment after repair (risk of power loss).

• 🔧 Recommended Tools:

  • Digital multimeter.

  • Advanced diagnostic tool (e.g., Autel MaxiCOM, Launch X431).

• 📚 Refer to the service manual for exact resistance/voltage values.

Note: If the code reappears after repair, check the throttle body wiring (possible interference).