P0731 Gear 1 Incorrect Ratio
The transmission is slipping or not holding the expected ratio in gear 1.
Common causes
- Low or degraded fluid
- Worn clutch pack
- Faulty shift solenoid or valve body
Symptoms
- Slipping
- Flare when shifting into gear 1
- Limp mode
What to check
- Check fluid level and condition
- Check for related solenoid codes
- Have the transmission inspected
Manufacturers may add their own detail to generic codes. If your vehicle shows a different description for P0731, follow the service information for that make and model.