AutoCodes – Generic – P0734

P0734 Code - Gear 4 Incorrect ratio

Quick Answer

This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows: Torque converter slip ratio = A x C/B A: Output shaft revolution signal from revolution sensor B: Engine speed signal from Engine Control Module (ECM) C: Gear ratio determined as gear position which TCM supposes If the actual gear position is higher than the position (4th) supposed by TCM, the slip ratio will be more than normal. Common causes include Low transmission fluid level, Dirty transmission fluid, Shift solenoids. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0734 indicates Gear 4 Incorrect ratio.
Common causes: Common causes include Low transmission fluid level, Dirty transmission fluid, Shift solenoids.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 54,047

How popular is this code, among other codes? Medium

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0734 Description

This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is higher than the position (4th) supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.

OBDII Code P0734 - Gear 4 Incorrect ratio - AutoCodes.com — P0734 Code - Gear 4 Incorrect ratio

What does this mean?

What are the Possible Causes of the DTC P0734?

Low transmission fluid level
Dirty transmission fluid
Shift solenoids
Transmission mechanical problems
Transmission hydraulic control circuit

How to Fix the DTC P0734?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

Start by inspecting the transmission fluid level and condition, and change fluid if necessary.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0734 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0734 code?

Need more information on how to fix the P0734 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0734 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P0734 Acura — Problem In 4th Clutch And 4th Clutch Hydraulic Circuit
P0734 Audi — Gear 4 Incorrect Ratio
P0734 BMW — Gear 4 Incorrect ratio
P0734 Chevrolet — Transmission 4th Gear Ratio Incorrect
P0734 Chrysler — Gear Ratio Error In Fourth Gear
P0734 Dodge — Gear Ratio Error In Fourth Gear
P0734 Ford — Incorrect Fourth Gear Ratio
P0734 GMC — Transmission 4th Gear Ratio Incorrect
P0734 Honda — Problem In 4th Clutch And 4th Clutch Hydraulic Circuit
P0734 Hyundai — Fourth Gear Incorrect Ratio
P0734 Infiniti — 4th. Gear Malfunction
P0734 Jeep — Gear Ratio Error In Fourth Gear
P0734 KIA — Fourth Gear Incorrect Ratio
P0734 Land Rover — Gear 4 Incorrect Ratio
P0734 Lexus — Gear 4 Incorrect Ratio
P0734 Mazda — Fourth Gear Error
P0734 Mercedes-Benz — Gear 4 Incorrect ratio
P0734 MINI — Gear 4 Incorrect ratio
P0734 Mitsubishi — Gear 4 Incorrect Ratio
P0734 Nissan — 4th. Gear Malfunction
P0734 Saturn — Gear 4 Incorrect Ratio
P0734 Subaru — Gear 4 Incorrect Ratio
P0734 Suzuki — Gear 4 Incorrect Ratio
P0734 Toyota — Gear 4 Incorrect Ratio
P0734 Volkswagen — Gear 4 Incorrect Ratio

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0734 Code

1. What are common symptoms of OBDII code P0734 (Gear 4 Incorrect ratio)?

The common symptoms of code P0734 include difficulty shifting into or out of fourth gear, slipping gears, harsh shifting, and decreased fuel efficiency.

2. What are the possible causes of OBDII code P0734?

Possible causes of code P0734 include a faulty transmission solenoid, low transmission fluid level or quality, a malfunctioning transmission control module, or mechanical issues within the transmission.

3. How can I diagnose the OBDII code P0734?

Diagnosing code P0734 typically involves using an OBDII scanner to read the code, checking the transmission fluid level and condition, inspecting for any leaks, and conducting a thorough examination of the transmission components.

4. Can driving with OBDII code P0734 cause further damage to my vehicle?

Continuing to drive with code P0734 may lead to further damage to the transmission system, resulting in more costly repairs. It is advisable to address the issue promptly to prevent additional problems.

5. How serious is OBDII code P0734?

Code P0734 indicates a problem with the fourth gear ratio in the transmission. While the severity can vary, it is important to address this issue promptly to prevent potential transmission failure and ensure safe driving.

6. What are some repair tips for fixing OBDII code P0734?

Repair tips for addressing code P0734 may include checking and topping up the transmission fluid, inspecting and replacing any damaged wiring or connectors, testing and replacing the transmission solenoid, or seeking professional help for a comprehensive diagnosis and repair.

7. How much does it typically cost to repair OBDII code P0734?

The cost of repairing code P0734 can vary depending on the specific cause of the issue, the extent of the damage, and labor costs. Repair expenses may range from a few hundred to over a thousand dollars, so it is advisable to get multiple quotes from reputable mechanics.

8. Can I reset the OBDII code P0734 on my own?

Resetting the OBDII code P0734 can be done using an OBDII scanner or by disconnecting the vehicle's battery for a few minutes. However, it is important to address the underlying issue causing the code before clearing it to prevent future problems.

9. How can I prevent OBDII code P0734 from occurring in the future?

Regular maintenance of your vehicle's transmission, including checking and changing the transmission fluid as recommended, can help prevent issues like code P0734. Additionally, driving responsibly and avoiding aggressive driving behaviors can also contribute to the longevity of your transmission.

10. Is it safe to continue driving my vehicle with OBDII code P0734 if it seems to be running fine?

Even if your vehicle appears to be running fine with code P0734, it is not recommended to ignore the issue. Driving with a transmission problem like this can lead to further damage and potentially unsafe driving conditions. It is best to address the problem promptly to avoid costly repairs and ensure your safety on the road.