Automatic gearbox

P0731 Automatic gearbox: wrong gear ratio (slipping) (gear 1)

By: Diagno editorial team · Updated: 2026-10-15

P0731 means: Automatic gearbox: wrong gear ratio (slipping) (gear 1). The automatic gearbox module has found a fault. Drive gently and have the car checked soon. The most common repair costs about €70–140 in Estonia, depending on make and model. The most common cause: gearbox oil low or old.

Is it safe to drive?Get it checked soonDrive gently and have the car checked soon.

Oil change€70–140parts and labour in Estonia, depending on make and model

What it means

The automatic gearbox module has found a fault. The gearbox may go into limp mode: it holds one gear and shifts harshly or not at all.

What you may notice

Stuck in one gear (limp mode)
Harsh or late gear changes
Gearbox slipping
Engine or gearbox light on

What could be wrong

1Gearbox oil low or old · Oil change €70–140
2Gearbox solenoid or valve body · Gearbox solenoid replacement €250–500
3Gearbox module or wiring · Control unit check and software €150–300
4Internal wear · Gearbox repair €600–1200

Repair difficulty: Hard

What you can check yourself

Read the gearbox module's own codes too. If the gearbox slips, drive gently and don't tow a trailer. Best left to a workshop. It needs a diagnostic tool and experience.

How we fix it

We read all gearbox codes and data
We check oil level and condition
We check connectors and wiring
We replace the solenoid, sensor or oil, or repair the gearbox

Standard SAE description: Gear 1 Incorrect ratio

This code usually comes with: Check engine lightSee what the light means →

Want a definite answer?

Bring the car to our workshop in Estonia for diagnostics. We read the fault codes, test the sensors and tell you what is wrong. Repair price depends on the work involved, generally €45 per hour.

Book a diagnostic check

Questions

What does fault code P0731 mean?

Automatic gearbox: wrong gear ratio (slipping) (gear 1). The automatic gearbox module has found a fault. The gearbox may go into limp mode: it holds one gear and shifts harshly or not at all.

Can I drive with code P0731?

Drive gently and have the car checked soon.

How much does it cost to fix P0731?

It depends on the cause: oil change €70–140; gearbox solenoid replacement €250–500; control unit check and software €150–300. Prices include labour at €45/h, depending on make and model.

How is P0731 fixed?

We read all gearbox codes and data. We check oil level and condition. We check connectors and wiring. We replace the solenoid, sensor or oil, or repair the gearbox.

Based on AI combined with our hands-on workshop experience and knowledge. This information is general and prices are approximate (Estonian workshop rates). The same code can mean different things on different cars. Only an inspection of the car gives a definite answer.