P0730 reports a wrong transmission ratio without assigning it to a gear. Two uses are documented. Older Aisin-type automatics (a 2006 GM table, Saab's 9-5 of 2002) set it when fourth or fifth gear shows the ratio of third – a shift solenoid (Saab: S3) is not switching; GM lights the MIL at once, Saab enters limp mode. GM's continuously variable transmissions of 2023 and 2025 use it when the pulleys do not reach the commanded variator ratio – the belt or chain slips or clamping pressure is too low – after one trip. Ford and newer GM step automatics use gear-specific or clutch valve codes instead. Check fluid level and condition first.
High severity. Can I keep driving?Continuing is not recommended: if the transmission slips, it can overheat, break, and leave you without drive power while moving. If you have no other option, drive very gently and only a short distance, or use a tow truck.
Symptoms
- Slipping, engine speed rises without drive
- Wrong gear or missing upper gears, limp mode
- Check engine light (GM) or transmission warning
- CVT: judder, weak acceleration
Most likely causes
- Fluid level or quality (CVT fluid or ATF)
- Shift solenoid or pressure control valve sticking or faulty
- Clutch or brake wear, or worn variator belt, chain or pulleys
- Faulty speed sensor signal
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: hard
- It can trigger limp mode.
- It affects emissions.
What each character of P0730 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 7: Transmission
- 30: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0730?
Continuing is not recommended: if the transmission slips, it can overheat, break, and leave you without drive power while moving. If you have no other option, drive very gently and only a short distance, or use a tow truck.
What causes code P0730?
The most common causes are: fluid level or quality (CVT fluid or ATF); shift solenoid or pressure control valve sticking or faulty; clutch or brake wear, or worn variator belt, chain or pulleys.
Related codes
- P0731Gear 1 Incorrect Ratio
- P0732Gear 2 Incorrect Ratio
- P0733Gear 3 Incorrect Ratio
- P0734Gear 4 Incorrect Ratio
- P0735Gear 5 Incorrect Ratio
- P0736Reverse Incorrect Ratio
Sources
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.