P0731 – Gear 1 Incorrect Ratio

Description

The ECM detects an incorrect gear ratio in 1st gear.

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Symptoms

  • Slipping
  • Harsh shifting
  • Limp mode

Causes

  • Low fluid
  • Worn clutches
  • Valve body issues

Diagnosis

  • Check fluid level
  • Monitor gear ratio data
  • Inspect valve body

Repair

  • Refill fluid
  • Service valve body
  • Rebuild transmission