P2122 - Throttle/Pedal Position Sensor/Switch 'A' Circuit Low Input: Common Issues in Ford and Honda Models

Quick Answer

P2122 means: DTC P2122 indicates a low input signal from the throttle position sensor, affecting engine performance.

Fix: Check and replace faulty components Cost: $150 - $300 Time: 90-180 minutes

Can I drive with P2122? Immediate attention is recommended to prevent further damage.

Common Questions

What does P2122 mean and how does it affect my car?

DTC P2122 indicates that the throttle position sensor is not sending the correct signal to the vehicle's computer. This can lead to poor acceleration and engine performance issues, making it crucial to address promptly.

What are the most common causes of P2122 and how much does it cost to fix?

Common causes include a faulty throttle position sensor, damaged wiring, and a malfunctioning accelerator pedal position sensor. Repair costs can range from $150 to $300 depending on the specific issue.

Can I drive my car with P2122 or should I stop immediately?

It is not recommended to drive your vehicle with this code, as it can lead to unsafe driving conditions due to poor acceleration and potential stalling.

How can I diagnose P2122 myself using GeekOBD APP?

Using the GeekOBD APP, you can scan for codes, check freeze frame data, and monitor the throttle position sensor's readings to understand the problem better.

What vehicles are most commonly affected by P2122?

DTC P2122 is often seen in models like the 2016 Honda Civic and 2015 Ford F-150, especially those with high mileage or older components.

How can I prevent P2122 from happening again?

Regular maintenance, including cleaning the throttle body and checking electrical connections, can help prevent this issue from recurring.

What is P2122?

The Diagnostic Trouble Code (DTC) P2122 refers to a problem with the throttle or pedal position sensor/switch circuit, specifically indicating a low input signal. This code often triggers when the Engine Control Module (ECM) detects that the signal from the throttle position sensor is below the expected range. In simpler terms, the vehicle's computer isn't receiving the correct data about the position of the accelerator pedal, which can lead to performance issues. For instance, if you own a 2016 Honda Civic or a 2015 Ford F-150, you may experience symptoms like poor acceleration or stalling. The throttle position sensor is crucial for proper engine management, as it communicates the driver's intent based on how far the pedal is pressed. When this code appears, it can significantly hinder your vehicle's performance, making it essential to address promptly. Ignoring this issue can lead to further complications, including diminished fuel efficiency and potential engine damage. Therefore, understanding this code and its implications can help you maintain your vehicle's health and performance effectively.

System: P - Powertrain (Engine, Transmission, Emissions)

Symptoms

Common symptoms when P2122 is present:

  • Check engine light illuminates and remains on, indicating an issue that needs diagnostics.
  • Engine may hesitate or stall during acceleration, which can be particularly dangerous in traffic.
  • Fuel economy may drop significantly, resulting in a decrease of 10-15% in miles per gallon.
  • Unstable idle when the vehicle is at a stop, leading to vibrations or rough engine performance.
  • Difficulty in accelerating smoothly, often requiring more pressure on the gas pedal than usual.

Possible Causes

Most common causes of P2122 (ordered by frequency):

  1. The most common cause is a faulty throttle position sensor, which has a likelihood of about 60%. This sensor can wear out over time or suffer from corrosion.
  2. Another frequent culprit is damaged wiring or connectors in the throttle position sensor circuit, which can lead to poor signal transmission.
  3. A third cause is a malfunctioning accelerator pedal position sensor, often due to dirt or debris buildup, which can be prevented with routine cleaning.
  4. Less common but serious causes include a failing ECM, which can lead to incorrect readings and requires extensive diagnostics.
  5. A rare but possible cause could be software issues within the vehicle’s computer system, which may need a software update or reprogramming.

P2122 Repair Costs

Cost Breakdown by Repair Type

Throttle Position Sensor Replacement

Replacing the faulty throttle position sensor with a new OEM part.

  • Total: $150 - $300
  • Success rate: 90%
Wiring Repair

Repairing or replacing damaged wiring or connectors in the throttle position sensor circuit.

  • Total: $100 - $200
  • Success rate: 85%
Money-Saving Tips for P2122
  • Start with the most common and least expensive repairs first
  • Use GeekOBD APP to confirm diagnosis before replacing expensive parts
  • Consider preventive maintenance to avoid future occurrences
  • Compare prices for OEM vs aftermarket parts based on your needs
  • Address the issue promptly to prevent more expensive secondary damage

Diagnostic Steps

Professional P2122 Diagnosis Process

Follow these systematic steps to accurately diagnose P2122. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes)
GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes)
GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 3: Component testing - Use a multimeter or specific diagnostic tools to test the throttle position sensor and associated wiring (20-30 minutes)
GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 4: System function test - Verify proper operation after repairs and clear codes using the GeekOBD APP (10-15 minutes)
GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success (15-20 minutes)
GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.

Important Notes

  • Always verify the repair with GeekOBD APP after completing diagnostic steps
  • Clear codes and test drive to ensure the problem is resolved
  • Address underlying causes to prevent code recurrence

Real Repair Case Studies

Case Study 1: Throttle Position Sensor Replacement in a 2016 Honda Civic

Vehicle: 2016 Honda Civic, 50,000 miles

Problem: Customer reported check engine light and poor acceleration.

Diagnosis: Diagnostic scan revealed DTC P2122; throttle position sensor was tested and found faulty.

Solution: Replaced the throttle position sensor and cleared the error codes.

Cost: $220 (sensor replacement and labor)

Result: Customer reported improved acceleration and the check engine light remained off.

Case Study 2: Wiring Repair for a 2015 Ford F-150

Vehicle: 2015 Ford F-150, 75,000 miles

Problem: Vehicle hesitated during acceleration and check engine light was on.

Diagnosis: Found exposed wires in the throttle position sensor circuit causing low input signal.

Solution: Repaired the wiring and secured connections to prevent future issues.

Cost: $150 (wiring repair and labor)

Result: Vehicle performance was restored, and no further codes appeared.

Diagnose P2122

Use GeekOBD APP for professional diagnosis!

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  • Advanced diagnostic features
  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: P2122
System: Powertrain (Engine, Transmission, Emissions)
Severity: HIGH
Category: Engine Codes