P0843 - Transmission Fluid Pressure Sensor Circuit Range/Performance Problem

Quick Answer

P0843 means: The P0843 code indicates a malfunction in the transmission fluid pressure sensor circuit.

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

Can I drive with P0843? Immediate attention is recommended to prevent further transmission damage.

Common Questions

What does P0843 mean and how does it affect my car?

The P0843 code indicates a problem with the transmission fluid pressure sensor circuit, which is crucial for the proper functioning of your vehicle's transmission. If this issue persists, you may experience erratic shifting, slipping, or even total transmission failure, impacting your vehicle's performance and safety.

What are the most common causes of P0843 and how much does it cost to fix?

Common causes of the P0843 code include a faulty transmission fluid pressure sensor, wiring issues, low transmission fluid levels, and in rare cases, internal mechanical problems. Repair costs can range from $150 to $300 for sensor replacement, depending on the specific issue and vehicle.

Can I drive my car with P0843 or should I stop immediately?

While it may be possible to drive short distances with a P0843 code, it is not advisable. Ignoring the code can lead to severe transmission damage, resulting in costly repairs. It’s best to have the issue diagnosed and repaired promptly.

How can I diagnose P0843 myself using GeekOBD APP?

Using the GeekOBD APP, you can perform a full OBD2 scan to retrieve the P0843 code and any related codes. The app provides freeze frame data, allowing you to see the vehicle's conditions when the code was triggered, which helps in pinpointing the issue.

What vehicles are most commonly affected by P0843?

The P0843 code is commonly reported in models such as the 2013-2018 Chevrolet Silverado, 2015-2019 Ford F-150, and various Honda Accord models from 2013-2017. Always check for any recalls or Technical Service Bulletins (TSBs) related to the transmission system for these vehicles.

How can I prevent P0843 from happening again?

To prevent the P0843 code from recurring, ensure regular maintenance of your vehicle's transmission system, including fluid changes and inspections. Address any leaks immediately and consider using high-quality transmission fluid to enhance performance.

What is P0843?

The P0843 code indicates a problem with the transmission fluid pressure sensor circuit, specifically, it means that the Powertrain Control Module (PCM) has detected an issue with the performance or range of the signal from the transmission fluid pressure sensor. This sensor is crucial for the proper functioning of your vehicle's transmission system, as it helps in monitoring the fluid pressure and ensuring that the transmission operates smoothly. When this code appears, it can lead to various transmission-related issues, such as erratic shifting, slipping, or even total transmission failure if left unaddressed. Car owners should be aware that this code is often accompanied by other codes related to transmission performance, and it can affect a range of vehicles, including popular models like the 2013-2018 Chevrolet Silverado and the 2015-2019 Ford F-150. Ignoring this code may result in decreased fuel efficiency and could potentially lead to more expensive repairs down the line. It’s essential to address the problem promptly to maintain your vehicle's performance and longevity.

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

Symptoms

Common symptoms when P0843 is present:

  • Check engine light illuminates and stays on, signaling an issue with the transmission.
  • Transmission may slip or hesitate during acceleration, creating a jarring driving experience.
  • Fuel economy drops significantly, often by 10-20%, due to improper transmission function.
  • Rough shifting or delayed engagement when changing gears, especially noticeable in automatic transmissions.
  • Possible overheating of the transmission, leading to the risk of severe damage.

Possible Causes

Most common causes of P0843 (ordered by frequency):

  1. Faulty transmission fluid pressure sensor (most common cause, approximately 50% likelihood). This sensor can fail due to age or contamination.
  2. Wiring issues such as damaged, corroded, or loose connections in the sensor circuit can lead to signal problems.
  3. Low transmission fluid levels caused by leaks or inadequate maintenance, which can affect sensor readings.
  4. Faulty PCM or software issues that may misinterpret the sensor's data and trigger the P0843 code.
  5. In rare cases, mechanical problems within the transmission itself, such as worn gears or clutches.

P0843 Repair Costs

Cost Breakdown by Repair Type

Transmission Fluid Pressure Sensor Replacement

Replacing the faulty transmission fluid pressure sensor to restore normal operation.

  • Total: $150 - $300
  • Success rate: 80%
Wiring Repair

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

  • Total: $100 - $200
  • Success rate: 70%
Transmission Fluid Change

Changing the transmission fluid to ensure proper lubrication and sensor function.

  • Total: $80 - $150
  • Success rate: 75%
Money-Saving Tips for P0843
  • 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 P0843 Diagnosis Process

Follow these systematic steps to accurately diagnose P0843. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Initial visual inspection - Check for signs of damaged wiring, loose connections, or fluid leaks around the transmission (5-10 minutes)

Step 1: Initial visual inspection - Check for signs of damaged wiring, loose connections, or fluid leaks around the transmission (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 and any related codes (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context and any related codes (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 voltage and resistance of the transmission fluid pressure sensor (20-30 minutes)

Step 3: Component testing - Use a multimeter to test the voltage and resistance of the transmission fluid pressure sensor (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 - After repairs, verify the proper operation of the transmission and clear codes using the GeekOBD APP (10-15 minutes)

Step 4: System function test - After repairs, verify the proper operation of the transmission 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 ensure that the transmission functions properly and the code does not return (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to ensure that the transmission functions properly and the code 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: Successful Repair of P0843 in a 2015 Ford F-150

Vehicle: 2015 Ford F-150, Mileage: 80,000 miles

Problem: Customer reported check engine light illuminated and rough shifting.

Diagnosis: Performed OBD2 scan with GeekOBD APP, retrieved P0843 and related codes. Visual inspection revealed damaged wiring.

Solution: Replaced the damaged wiring and transmission fluid pressure sensor, performed fluid change.

Cost: $300 (parts: $150 for sensor, $150 for labor)

Result: Post-repair, vehicle shifted smoothly, and check engine light was cleared.

Case Study 2: Transmission Fluid Pressure Sensor Replacement on 2017 Chevrolet Silverado

Vehicle: 2017 Chevrolet Silverado, Mileage: 60,000 miles

Problem: Customer experienced transmission slipping and poor fuel economy.

Diagnosis: Used GeekOBD APP to confirm P0843 code and conducted a fluid level check, which was low.

Solution: Replaced the transmission fluid pressure sensor and topped off the transmission fluid.

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

Result: After the repair, the customer reported improved transmission performance and fuel efficiency.

Diagnose P0843

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: P0843
System: Powertrain (Engine, Transmission, Emissions)
Severity: HIGH
Category: Engine Codes