Trouble codes › P0731

P0731 Gear 1 Incorrect Ratio

Transmission

P0731 means the transmission is slipping in first gear.

In first gear, the input and output speeds don't match the first-gear ratio: the transmission is slipping in first or not fully engaging it.

Can I keep driving? Not if you can avoid it.

Drive as little as possible. Slipping wears the transmission quickly.

Common causes

  1. Low or burnt fluid
  2. Worn first-gear clutch or band
  3. A shift solenoid or valve body problem
  4. A speed sensor reading wrong

Symptoms

  • Slipping or flare when pulling away
  • Delayed engagement into Drive
  • Limp mode

What to check first

  1. Check fluid level and condition.
  2. Check for solenoid or speed sensor codes.
  3. Look for service bulletins and software updates.
  4. Have a transmission shop diagnose it if fluid and sensors check out.

What does P0731 mean on your vehicle?

The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.

Ask iRepair about P0731

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Related codes

General guidance for P0731 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.