P0730: Incorrect Gear Ratio OBD-II Trouble Code

In This Guide

The P0730 OBD-II code is a generic trouble code, meaning it applies to all makes & models of vehicles from 1996 to present. It can be caused by anything from shift solenoid problems to dirty transmission fluid. We will explore this trouble code more closely below.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

What Does P0730 Mean?

“Transmission Control System Malfunction” is the definition of OBD-II Trouble Code P0730.

By automatically selecting different “speeds” or gear ratios to deliver power to the wheels, an automatic transmission’s goal is to match the optimal torque and power characteristics of the engine to the desired speed and rate of acceleration of the driver.

When the TCM (or transmission control module) sees an RPM difference (rotational speed) between the transmission output RPM sensor and input RPM sensor that is greater than a certain value, the P0730 code is triggered. This can happen while shifting between gears or when driving at a steady speed in a particular gear.

Symptoms of P0730

  • Illumination of the Check Engine light
  • Fuel economy decreases
  • Shifting of the vehicle is delayed or goes into wrong gear
  • Transmission slipping
  • There may be misfire-like symptoms, dying when coming to a stop after freeway driving, or other performance issues in some cases
  • The driver may not notice any adverse conditions in some cases

Common Causes of P0730

  • Faulty torque converter clutch
  • Faulty shift solenoids
  • Blockage on the inside of the transmission main control
  • Internal mechanical failure of the transmission
  • Blockage in fluid lines
  • Clogged fluid filter or worn pump
  • Dirty or low transmission fluid

How to Diagnose the P0730 Code?

The level of fluid in the transmission should be noted and checked for quality before doing any other diagnostic tests. You should replace any dirty or old fluid.

In the hands of a qualified mechanic, an OBD-II scanner diagnoses the P0730 code. With this, they can view any needed info from the engine in real-time. The technician will take the vehicle for a test drive after clearing the code.

The code is due to an actual condition within the transmission if it comes back again. To determine if the engine stall speed fits factory specifications, the mechanic might perform a torque converter stall speed test.

Common Mistakes When Diagnosing

Common misdiagnoses include an internal transmission problem and engine misfire. The symptoms you are experiencing may simply be due to dirty or low transmission fluid. The transmission problems that are causing the trouble code may be resolved by simply replacing or topping off the fluid.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

What Repairs Will Fix the P0730 Code?

  • Wires connecting sensors to the transmission control module and other electrical connections should be inspected.
  • Any damaged or corroded wires in and near the transmission control module should be repaired or replaced.
  • Parts in the transmission might need to be repaired or replaced if the transmission wiring and fluid are all in working condition.
  • The transmission must be removed if there is a problem with the torque converter, shift solenoids, or pump.
  • To be sure that it operates without the P0730 code or any other trouble codes, the transmission should be reinstalled and inspected once the needed repairs are completed and before testing.

Codes Related to P0730

  • P0729
  • P0731
  • P0732
  • P0733
  • P0734
  • P0735
  • P0736

Need more help with a P0730 code?

If the above guide does not answer your questions, comment below with the code(s) and symptoms you are getting along with the make, model, and year of your car.

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Nolly (Duke) Sams
1 year ago

What could be the cause of a 2016 Chrysler 200 as you takeoff it does a little shimmy when you push the pedal and it appears to shift to the next gear? But not every time.

Chad
1 year ago

P0730 code but no 4th gear

Mark J Quigley
1 year ago

I have a 2002 Honda Civic with 1.7 litre engine. I’m getting code po 730 only when the transmission is warmed up. All gears are lost, but if I turn the car off and back on again it will drive fine. What do you think could be the problem? Thanks.

Anonymous
1 year ago
Reply to  Mark J Quigley

Sounds like the trans cooler.

Anonymous
1 year ago

no check engine light but was in limp mode. i turned around on the road coming back home & she started jerking let off the gas then slowly pushed the pedal alittle i knew she was gonna limp me home. dot my diablo tuner out & checked codes & had 2nd gear incorrect gear ratio but no light. fluid is in the tranny its pink bright pink smells a lil funny but not burnt?i cleared the code but have not drove her any?

Jay
1 year ago

Code p0730 incorrect gear ratio

John Hampton
1 year ago

Won’t shift out of first high rpm without the speed comparison

Terry
1 year ago

It has trouble with up shifting as well as down shifting from 2nd. I have replaced the transmission fluid and filter.and pan seal. But same issue, I was wondering if it could be the shift solenoids ? And what should I do to fix it?

Jesse Roxas
1 year ago

The code is P0733 for my 2016 RAM 1500 Rebel. Can this issue be corrected with minor repairs?

Marcia
1 year ago

My 2012 Jeep Compass Sport has TCM trouble codes: P0730, P0741 & P0777. I would like to know if I can still drive the car and a estimate on what repair would cost. Thank you!

Shawna Nichols
1 year ago

My ,2008 dodge avenger won’t shift into any forward gear.. only reverse

Nolly (Duke) Sams
1 year ago
Reply to  Shawna Nichols

I have the same problem. My transmission will only go in reverse and not forward it by 2006 GMC SUV.

Shawna Nichols
1 year ago

My 2008 dodge avenger won’t go into a forward gear at all..

Fred
1 year ago

My 2011Jeep Compass had aPO777and aPO746 code I changed my filters and transmission fluid it ran awesome for a couple of days then got a new code PO730 incorrect gear ratio I changed the valve body and it still stuck in low gear it won’t shift out of low gear any help with this problem thank you

Floyd Smith
2 years ago

2003 honda pilot it has codes p0730,p0740,p0780 the tranny is slipping won’t shift into 2nd to 3rd gear then when I get to 40 mph let off gas it will jerk really hard n down shift hard I changed the fluid and still doing it the d starts flashing and sometimes I lose reverse it has high rpms n won’t shift

Shane Parr
2 years ago

P0700 and P0730
98 civic lx automatic transmission
Little bit of high idle
Acts like it goes to neutral and stays
Erratic shifting
Doesn’t seem to go into overdrive
Trans slipping when giving it gas
Changed tranny fluid
Cleaned iacv and throttle body
Cleaned solenoids

Please someone help it’s been horrible

Kristi Marie
2 years ago

My 2006 Dodge Charger LX 3.5 L v6 with a Nag 1 wont shift pass 2nd sometimes 3rd gear and slips out of gear if you accelerate to quickly and you have to pull over and kill the car and restart it to make it. shift back into gear… I have replaced the valve body,conductor plate, all 6 solenoids, and both speed sensors, the connector on the outside of the transmission , the gasket and trans filter. I have not replaced the actual plug yet but I did do a continuity test and only the top middle center hole has a closed circuit . Idk if that is normal or if every hole is suppose to have a closed circuit. Plz help me I am getting P0700, from the Engine and P0730 P0731, P0734 codes .from the AT it has gone from 6 codes on the AT (Nag1) to only the three incorrect gear ratio codes .

Last edited 2 years ago by Kristi Marie
Pheng Her
2 years ago

2001 Honda odyssey Everything start up but when you put in gear doesn’t wanna go

Last edited 2 years ago by Pheng Her
Laterius
2 years ago

I’m getting come p0730 on my 2012 Dodge Charger rt the check engine light is on I need help

David Flakes
2 years ago
Reply to  Laterius

What ended up being the problem?

Josh
1 year ago
Reply to  David Flakes

What happened? I have same thing going on with mine

Traci Boatwright
1 year ago
Reply to  Josh

I’m having the same issue with my 2012 dodge charger srt8 code 730 and my transmission is slamming into the next gears when shifting from reverse to drive. Also stalls out at 60 mph

Anonymous
2 years ago

No 4 th or 5th gear on 2007 dodge Magnum

Kendall
3 years ago

I have 2011 Dodge Durango citadel it’s in park position but on dashboard reads 2nd gear it want start either was wondering can dirty fluids cause this or solenoid need to be changed

Catherine
3 years ago

It is a 2000 Grand Prix GTP Supercharged

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