P0929 - Transmission Range Sensor Circuit Range/Performance Problem in Honda, Nissan, and Toyota Vehicles

Quick Answer

P0929 means: P0929 indicates a problem with the transmission range sensor circuit.

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

Can I drive with P0929? Address this issue immediately to avoid further transmission damage.

Common Questions

What does P0929 mean and how does it affect my car?

The P0929 code indicates a transmission range sensor problem, which can lead to issues like starting difficulties and erratic shifting. This affects vehicle safety and performance if not addressed.

What are the most common causes of P0929 and how much does it cost to fix?

Common causes include a faulty transmission range sensor, damaged wiring, or low transmission fluid. Repair costs can range from $100 to $300 depending on the specific issue.

Can I drive my car with P0929 or should I stop immediately?

It is not recommended to drive your vehicle with this code, as it could lead to serious transmission damage. It's best to address the issue promptly to avoid further complications.

How can I diagnose P0929 myself using GeekOBD APP?

You can use the GeekOBD APP to scan for codes, view freeze frame data, and perform system tests. This will help you understand the context of the issue and guide your repair decisions.

What vehicles are most commonly affected by P0929?

Commonly affected vehicles include 2015-2018 Honda Civics, 2013-2017 Nissan Altimas, and 2014-2019 Toyota Corollas, among others. Always check for any recalls or TSBs related to your model.

How can I prevent P0929 from happening again?

Regular maintenance of your vehicle, including checking transmission fluid levels and ensuring electrical connections are secure, can help prevent this issue from recurring.

What is P0929?

The diagnostic trouble code (DTC) P0929 indicates a transmission range sensor circuit range/performance problem. This code typically arises in vehicles equipped with automatic transmissions, particularly in models from Honda, Nissan, and Toyota. The transmission range sensor, also known as the neutral safety switch, is crucial for determining the current gear position of the transmission. It sends signals to the engine control module (ECM), allowing the vehicle to start and operate correctly. When the ECM detects a discrepancy between the expected range and the actual sensor input, it triggers the P0929 code. This situation can lead to a range of issues including difficulty in starting the vehicle, erratic shifting, or even engine stalling. Owners may notice the 'Check Engine' light illuminating on the dashboard, and in some cases, the vehicle may enter limp mode, where performance is limited to prevent further damage. If left unaddressed, a malfunctioning transmission range sensor can lead to more severe transmission issues, resulting in costly repairs. It’s essential for drivers experiencing symptoms related to this code to seek timely diagnostic and repair solutions.

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

Symptoms

Common symptoms when P0929 is present:

  • The 'Check Engine' light remains illuminated on the dashboard, indicating a malfunction that needs attention.
  • The engine struggles to start or fails to start, which can be frustrating and may leave you stranded.
  • Shifting gears becomes erratic, with noticeable delays or harshness during transitions, impacting driving comfort.
  • Limp mode activation occurs, where the vehicle limits power to protect the transmission, preventing normal operation.
  • Fuel economy may decrease by 10-20%, as the vehicle works harder to compensate for transmission issues.

Possible Causes

Most common causes of P0929 (ordered by frequency):

  1. The most common cause of code P0929 is a faulty transmission range sensor, with a likelihood of about 60%. This sensor can wear out due to heat and age, leading to inaccurate readings.
  2. A second possible cause is damaged wiring or connectors in the transmission range sensor circuit. This can lead to intermittent signals to the ECM, making diagnosis tricky.
  3. Another potential cause is low transmission fluid levels or dirty fluid, which can affect sensor operation. Regular maintenance can help prevent this issue.
  4. Less common but serious is a malfunctioning ECM, which may misinterpret signals and cause erratic behavior. This is usually diagnosed after other causes have been ruled out.
  5. A rare cause could be a mechanical issue within the transmission itself, such as stuck gears or internal damage, which would require extensive repairs.

P0929 Repair Costs

Cost Breakdown by Repair Type

Transmission Range Sensor Replacement

Replacing the faulty transmission range sensor to restore normal function.

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

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

  • Total: $100 - $200
  • Success rate: 80%
Money-Saving Tips for P0929
  • 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 P0929 Diagnosis Process

Follow these systematic steps to accurately diagnose P0929. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes)

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: Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes)

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: Step 3: Component testing - Use a multimeter to test the transmission range sensor for proper voltage and resistance (20-30 minutes)

Step 3: Component testing - Use a multimeter to test the transmission range sensor for proper voltage and resistance (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: Step 4: System function test - Verify proper operation after repairs and clear codes using the GeekOBD APP (10-15 minutes)

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: Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and ensure the 'Check Engine' light does not return (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and ensure the 'Check Engine' light does not return (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: Transmission Range Sensor Replacement in a 2016 Honda Civic

Vehicle: 2016 Honda Civic, 50,000 miles

Problem: Customer reported 'Check Engine' light and difficulty in shifting gears.

Diagnosis: Scanned for codes using GeekOBD APP, confirmed P0929. Inspected wiring and sensor functionality.

Solution: Replaced the faulty transmission range sensor and cleared the codes.

Cost: $250 (sensor $150, labor $100)

Result: Customer reported smooth operation and no recurrence of the issue.

Case Study 2: Wiring Repair in a 2014 Nissan Altima

Vehicle: 2014 Nissan Altima, 75,000 miles

Problem: Customer experienced erratic shifting and 'Check Engine' light.

Diagnosis: Used GeekOBD APP to identify P0929; inspected wiring and found corrosion.

Solution: Repaired the damaged wiring and secured connections.

Cost: $150 (labor $100, materials $50)

Result: Shifting issues resolved and vehicle returned to normal operation.

Diagnose P0929

Use GeekOBD APP for professional diagnosis!

  • Real-time data monitoring
  • Advanced diagnostic features
  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: P0929
System: Powertrain (Engine, Transmission, Emissions)
Severity: HIGH
Category: Engine Codes