P0730

Incorrect Gear Ratio

Q: Is it safe to drive with P0730?

Only gently and briefly. A wrong gear ratio usually means the transmission is slipping, which generates heat and can cause further damage. Get it diagnosed soon.

Q: Can I just clear P0730?

It returns as soon as the transmission slips again; clearing it doesn't fix the underlying fluid, solenoid, or mechanical problem.

Automatic transmission Generic OBD-II High

What it means

P0730 means the transmission controller has compared input and output speeds and found the gear ratio doesn't match the gear it commanded — the transmission is effectively slipping or not engaging the right gear. Common causes range from low fluid or a bad solenoid to internal wear, and continued driving while it slips generates heat and risks further damage.

High

Can I keep driving? Cautiously — slipping or a wrong gear ratio strains the transmission and can worsen; drive gently and get it checked promptly.

Real-world scan data

Seen in

154

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Transmission slipping or engine revving without matching acceleration
Harsh, delayed, or wrong-gear shifting
Transmission running hot

Common causes

Most likely first

Low or contaminated transmission fluidLikely
Faulty shift or pressure-control solenoidCommon
Worn clutches, bands, or internal transmission wearCommon
Failing torque converter or input/output speed sensor mismatchLess often

How to diagnose & fix

Work through it in order

Scan and read freeze-frame; check for accompanying solenoid or speed-sensor codes.
Check the transmission fluid level and condition first — low or burnt fluid is a common cause.
Test the shift and pressure-control solenoids and the speed sensors.
If the ratio is still wrong, the transmission likely needs internal inspection or service. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0730?+

Only gently and briefly. A wrong gear ratio usually means the transmission is slipping, which generates heat and can cause further damage. Get it diagnosed soon.

Can I just clear P0730?+

It returns as soon as the transmission slips again; clearing it doesn't fix the underlying fluid, solenoid, or mechanical problem.

Read & clear P0730 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX