P0735 Code: Gear 5 Incorrect Ratio

Reviewed by

Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on September 15th, 2023

Reading Time: 4 minutes
Summary
  • DTC P0735 stands for “Gear 5 Incorrect Ratio.”
  • It is logged when the TCM detects that the transmission is struggling to enter fifth gear or does not enter fifth gear correctly.
  • Code P0735 is commonly caused by internal transmission failure, a malfunctioning PCM, or TCM failure.
  • Symptoms of P0735 include a lit check engine light, poor fuel economy, and the inability to shift properly.

Trouble codes help alert you to potential problems that your vehicle might have. Find out what the P0735 code means and learn more about its common causes and symptoms with this brief guide.

What Does the P0735 Code Mean?

Diagnostic trouble code (DTC) P0735 stands for “Gear 5 Incorrect Ratio.” This trouble code sets when the transmission control module (TCM) detects that the transmission is not going into fifth gear correctly.

The trouble code P0735 sets when the transmission control module (TCM) detects that the transmission is not going into fifth gear correctly.

P0735 is triggered once your PCM detects that the RPM difference between the rotational speed of your input speed sensor and the transmission output speed sensor doesn’t match what the ECM/PCM expects to see in 5th gear.

The transmission helps manipulate the power produced by the engine and transfer that power to the drive wheels. It is controlled by the TCM, which is the transmission system’s main computer. The TCM uses solenoids to manipulate the fluid pressure that engages the different gears inside the transmission.

The P0735 code can appear in vehicles equipped with automatic transmissions that might have issues shifting into fifth gear. The TCM uses information from various sensors to monitor and ensure the transmission’s proper operation. If the TCM receives data from these sensors that do not match the required values, the P0735 code sets.

Plugging a scan tool into your vehicle’s OBD-II port allows you to see which codes are present. Driving with the P0735 code is not advised. It’s recommended that you take your vehicle to a repair shop for diagnosis and repairs as soon as possible. Incorrect gear ratio codes require specialized tools and advanced knowledge to fix, so it’s best to consult a certified mechanic.

To learn more about how codes like P0735 are set, read our discussion about OBD codes and gear ratios.

Note: The definition of code P0735 may be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Common Causes of the P0735 Code?

Like many other trouble codes, the P0735 has several possible causes. Below are some of the most common triggers of the P0735 code:

Low or contaminated transmission fluid can cause the P0735 code to register.

What are the Common Symptoms of the P0735 Code?

If you’re dealing with DTCs, you might notice several symptoms or none at all, depending on the situation. Below are some of the most common symptoms you might spot when the P0735 code is present:

  • Illuminated malfunction indicator lamp or check engine light
  • Increased fuel consumption
  • Inability to shift properly

How to Diagnose the P0735 Code

Many DTCs have multiple possible causes, and the P0735 code is no exception. In order to fix these codes properly, thorough troubleshooting or diagnosis is vital. Some diagnostic procedures require special tools and knowledge, to which you might not have easy access. In these cases, you will need a certified mechanic or technician to help you.

However, if you want to know more about why the P0735 code sets and how the troubleshooting process goes, there are many resources available.

Below is a video that explains the P0735 in more detail:

How to Fix the P0735 Code

As mentioned above, trouble codes have many possible causes and by extension, have multiple possible solutions. That means there is no single solution for every trouble code. This is why it’s important to conduct a thorough diagnosis first.

In addition, repair procedures differ depending on the vehicle’s manufacturer. A solution for the P0735 in an Audi vehicle might not work for a P0735 code in a Nissan. This is why consulting vehicle-specific repair manuals are important. While there are many auto repair guides and resources out there, repair manuals are still your best choice because they contain detailed information, helpful diagrams, and illustrations.

If you’re not confident in your trouble code repair know-how, it’s best to leave the job to a professional. Doing so helps you save time, effort, and money. It also prevents you from accidentally damaging your vehicle.

Other Notes About P0735

Other trouble codes related to the P0735 include P0730, P0731, P0732, P0733, P0734, and P0736.
If there are other transmission system-related codes, it’s recommended that you address those first before troubleshooting and fixing incorrect gear ratio codes like the P0735.

About The Authors
Reviewed By Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Richard McCuistian has worked for nearly 50 years in the automotive field as a professional technician, an instructor, and a freelance automotive writer for Motor Age, ACtion magazine, Power Stroke Registry, and others. Richard is ASE certified for more than 30 years in 10 categories, including L1 Advanced Engine Performance and Light Vehicle Diesel.

Written By CarParts.com Research Team

Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

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CarParts.com Research Team and Richard McCuistian, ASE Certified Master Automobile Technician