P2840 moderate

Gear Shift Fork 3 Position Circuit Range/Performance

The P2840 code means the vehicle's onboard diagnostic system has detected: Gear Shift Fork 3 Position Circuit Range/Performance. This is a moderate severity code.

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Keep driving?
No — stop driving
DIY difficulty
hard
Estimated cost
$300 - $1,200 (parts and labor)
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Common Symptoms

  • Erratic gear shifting
  • Transmission slipping between gears
  • Check Engine Light on
  • Reduced driving performance

Probable Causes (Ranked by Likelihood)

  • Worn gear shift fork 3 position sensor Very High
  • Shift fork 3 bent or damaged High
  • Low transmission fluid affecting hydraulic operation Moderate
  • TCM software needs update Low

Frequently Asked Questions

What does range/performance mean?

Range/performance indicates the sensor signal is outside expected parameters during normal operation, suggesting wear or mechanical issues with shift fork 3.

How is this diagnosed?

A mechanic uses scan tool live data to compare actual shift fork position against what the TCM commands during gear changes.

Will transmission fluid fix this?

While low fluid can contribute, this code usually indicates a mechanical or sensor issue that requires professional repair.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

  1. Read DTCs and monitor shift fork 3 position data

  2. Compare actual vs commanded shift fork position

  3. Inspect transmission fluid level and condition

  4. Test shift fork actuator operation

Sources 1

This page is built from documented references. Verify against your own service info before repair work.

  • SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)

Commonly Affected Vehicles

  • 2012-2020 Ford Focus (PowerShift)
  • 2010-2018 Volkswagen Jetta DSG
  • 2013-2020 Hyundai Elantra DCT
  • 2015-2020 Kia Soul DCT

Related Codes

P2839P2841

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