P2791: Low Gate Select Direction Circuit OBD-II Trouble Code


The P2791 OBD-II Trouble Code comes into play when the ECU assesses your chosen gear via the shifter, a process that influences engine timing, the fuel system, and transmission shift strategy. In instances where the ECU perceives an erroneous gear selection due to unusually elevated voltage levels on the gear shift direction circuit, it triggers a P2795 DTC.

Significance of a P2791 Code A P2791 diagnostic trouble code signifies a disparity in the ECU’s perception of the gear selected via the automatic transmission shifter. This misinterpretation can lead to a variety of transmission-related issues.

P2791 Symptoms & Problems

Common symptoms of a P2791 code include:

  1. Unusually harsh or abrupt gear shifts.
  2. Slippage between gears.
  3. Delayed gear transitions.
  4. Failure to engage specific gears.
  5. Diminished overall vehicle performance.
  6. Activation of limp mode.

What Causes of P2791 Codes?

  • Damaged wiring or connectors at the shifter
  • Malfunctioning shifter assembly or its components
  • Malfunction or misalignment of the transmission range sensor
  • A defective range sensor

How To Diagnose A P2791 Code

  • Inspect the condition of the wiring and connectors linking the transmission wiring harness to the shifter
  • Assess the functionality of the shifter itself, ensuring it operates as expected
  • Examine the transmission range sensor for potential misalignment or malfunction

How To Repairs or Fix A P2791 Code

  • Repair or replace any damaged wiring or connectors within the transmission circuit
  • Replace the shifter assembly if found to be faulty
  • Adjust or replace the transmission range sensor to ensure proper functionality

What Does It Cost to Diagnosing or Repair a P2791 Code?

The cost associated with diagnosing a P2791 trouble code varies:

  • If you possess a code reader, you can retrieve the code independently.
  • Alternatively, you can visit a local auto parts store where they may offer code reading services at no charge.
  • If you opt for a transmission repair shop, there may be a fee for code reading and subsequent diagnostic procedures. Costs can range from minimal to several hundred dollars depending on the extent of the diagnosis.