P0734 Subaru 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 Subaru 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.
Code P0734 Subaru Description
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.
What are the Possible Causes of the DTC P0734 Subaru?
- Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Transmission mechanical problems
- Transmission hydraulic control circuit
How to Fix the DTC P0734 Subaru?
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.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0734 Subaru 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.
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Frequently Asked Questions about P0734 Subaru Code
1. What does OBDII code P0734 on a Subaru mean?
Code P0734 indicates that there is an incorrect gear ratio in the transmission's fourth gear.
2. What are the common symptoms of OBDII code P0734 in a Subaru?
Common symptoms include difficulty shifting into or out of fourth gear, slipping when in fourth gear, delayed engagement, and the transmission may go into limp mode.
3. What are the possible causes of OBDII code P0734 in a Subaru?
Potential causes include low transmission fluid levels, dirty or contaminated transmission fluid, faulty shift solenoids, a worn clutch or clutch pack, damaged transmission components, or issues with the transmission control module.
4. How can I diagnose OBDII code P0734 in my Subaru?
Diagnosis typically involves checking the transmission fluid level and condition, conducting a visual inspection for any visible damage, performing a scan tool test to check for other trouble codes, and potentially conducting a road test to observe the transmission's behavior.
5. How can I repair OBDII code P0734 in my Subaru?
Possible repair options include topping up or changing the transmission fluid, replacing faulty shift solenoids, repairing or replacing damaged transmission components, addressing any clutch-related issues, and resetting the transmission control module.
6. Can driving with OBDII code P0734 in a Subaru cause further damage?
Continuing to drive with code P0734 present can potentially lead to further damage to the transmission components, so it is advisable to address the issue promptly.
7. Will resetting the check engine light make OBDII code P0734 go away?
Resetting the check engine light may temporarily clear the code, but if the underlying issue causing P0734 is not addressed, the code is likely to return.
8. Is it safe to continue driving my Subaru with OBDII code P0734?
Driving with code P0734 can be risky as it may result in transmission issues such as slipping or failure to engage gears properly. It's best to have the problem diagnosed and repaired as soon as possible.
9. How much does it typically cost to repair OBDII code P0734 in a Subaru?
The cost of repairing P0734 can vary depending on the specific cause of the issue, but it may range from a few hundred to over a thousand dollars, especially if significant transmission components need to be replaced.
10. Can I fix OBDII code P0734 in my Subaru myself, or should I take it to a professional mechanic?
While some simple maintenance tasks like checking and topping up transmission fluid can be done by DIY enthusiasts, diagnosing and repairing complex transmission issues associated with P0734 is usually best left to professional mechanics with the necessary expertise and tools.
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