Explanation of Code P2137: “Throttle/Pedal Position Sensor/Switch ‘D’/’E’ Voltage Correlation”
Severity
- Level: 🔴 High (risk of complete loss of throttle control).
- Urgency:
- Engine may stall while driving (immediate danger).
- Limp mode activated (reduced power).
Common Symptoms
- 🚨 Check Engine Light on (MIL) with code P2137.
- 🛑 Throttle stuck (engine RPM frozen).
- 🐌 Sudden loss of power (even at cruising speed).
- 🔄 Unstable idle or stalling at stop.
Main Causes
- Wiring issues:
- Corroded/deformed throttle body connector (“pigtail”).
- Wires shorted to ground or exposed wires.
- Electronic throttle body failure:
- Stuck gears (warped cover).
- Failed throttle motor.
- Faulty accelerator pedal sensor:
- Incorrect or intermittent signal.
- PCM/ECM error:
- Reprogramming needed (e.g., after throttle body replacement).
Diagnostic Procedure (Detailed Steps)
Step 1: Check Technical Service Bulletins (TSB)
- Example: TSB NTB14-058 for Nissan (stalling issues related to code P2137).
Step 2: Inspect the “Pigtail” Connector
- Location: On the throttle body (common models: Nissan Altima, Renault Mégane IV).
- Action:
- Disconnect and inspect the female terminals (corrosion, bent pins).
- Clean with CRC contact spray and apply dielectric grease.
Step 3: Test the Accelerator Pedal Sensor
- Multimeter:
- Measure voltage on the signal wire (0.5V to 4.5V progressive).
- If voltage jumps or is absent → Replace the sensor.
Step 4: Check the Throttle Body
- Remove the cover: Check plastic/metal gears for wear or binding.
- Throttle motor test:
- Direct 12V power → Throttle should open/close.
- If no movement → Throttle body is faulty.
Solutions & Costs
| Problem | Solution | Average Cost |
|---|---|---|
| Faulty throttle body | Replacement (new or used) | €200 – €800 |
| Failed pedal sensor | Replacement | €80 – €150 |
| Wiring repair | Replace “pigtail” connector | €30 – €100 |
| PCM reprogramming | At dealership | €100 – €300 |
Mistakes to Avoid
- ❌ Forcing gears: Risk of breaking plastic teeth.
- ❌ Forgetting the relearn procedure: Required after replacement (e.g., Nissan = 5 pedal presses).
Commonly Affected Models
- Nissan Altima (2013-2018): Recurring connector issues.
- Renault Mégane IV (1.2 TCe): Fragile throttle body.
- Toyota Camry (2015-2020): Pedal sensor failure.
Practical Case
- Problem: Code P2137 on a 2016 Nissan Altima with stuck throttle.
- Diagnosis: Corroded throttle body connector (oxidized terminals).
- Solution: Cleaning + connector replacement (€40).
Pro Tips
- Handle with care: The electronic throttle system is highly sensitive.
- Relearn procedure:
- Nissan: Ignition ON → 5 quick pedal presses → Wait 7s → Start.
If the code persists, consult a professional equipped with manufacturer diagnostic tools (e.g., Consult III+ for Nissan)! 🔧🚗⚠️