P0730 Mercedes-Benz Code - Incorrect Gear 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 speed sensor (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 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
- P0730 Mercedes-Benz indicates Incorrect Gear 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 P0730 Mercedes-Benz Description
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from speed sensor (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 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 P0730 Mercedes-Benz?
- Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Transmission mechanical problems
- Transmission hydraulic control circuit
How to Fix the DTC P0730 Mercedes-Benz?
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 P0730 Mercedes-Benz 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 P0730 Mercedes-Benz code?
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Frequently Asked Questions about P0730 Mercedes-Benz Code
1. What are the common symptoms of OBDII code P0730 (Incorrect Gear Ratio) in a Mercedes-Benz?
- Common symptoms include difficulty shifting gears, harsh shifting, delayed engagement, and the transmission slipping.
2. What are the possible causes of OBDII code P0730 in a Mercedes-Benz?
- Possible causes include a faulty transmission range sensor, low transmission fluid levels, a worn-out clutch or torque converter, or issues with the transmission control module.
3. How can I diagnose the OBDII code P0730 in my Mercedes-Benz?
- A thorough diagnosis involves scanning the vehicle for trouble codes, checking the transmission fluid levels and condition, inspecting the transmission components for wear, and performing a road test to observe the shifting behavior.
4. Can driving with OBDII code P0730 damage my Mercedes-Benz transmission?
- Continuing to drive with P0730 can potentially cause further damage to the transmission, leading to costly repairs. It is advisable to address the issue promptly.
5. What are some repair tips for fixing OBDII code P0730 in a Mercedes-Benz?
- Repair tips include ensuring the transmission fluid is at the proper level and condition, inspecting and replacing worn-out components like the clutch or torque converter, and reprogramming the transmission control module if necessary.
6. Is it safe to reset the OBDII code P0730 in my Mercedes-Benz without addressing the underlying issue?
- Resetting the code without fixing the root cause can temporarily clear the warning light but will not resolve the underlying transmission problem. It is important to address the issue to prevent further damage.
7. Can a DIY enthusiast fix OBDII code P0730 in a Mercedes-Benz, or is professional help recommended?
- While some DIY enthusiasts may be able to address simpler causes like low transmission fluid levels, diagnosing and repairing complex transmission issues typically require professional expertise to ensure proper resolution.
8. How much does it cost to repair OBDII code P0730 in a Mercedes-Benz?
- The cost of repair can vary depending on the specific cause of the code, the extent of the damage, and whether new parts are required. It is advisable to obtain a diagnostic from a professional to get an accurate estimate.
9. Are there any preventive maintenance measures to avoid OBDII code P0730 in a Mercedes-Benz?
- Regularly checking and changing the transmission fluid, avoiding aggressive driving habits, and following the manufacturer's recommended maintenance schedule can help prevent issues that may trigger code P0730.
10. Can extreme weather conditions affect the likelihood of OBDII code P0730 occurring in a Mercedes-Benz?
- Extreme temperatures can impact the performance of transmission components and fluid, potentially leading to issues that trigger code P0730. It is important to monitor the transmission's behavior in varying weather conditions.
Discuss the causes and fixes for P0730 Mercedes-Benz OBDII Code
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I have a Mercedes benz e320 it is a 1999 model have a 722.6 gearbox my car is stack in gear it only take revs and 2d gear did replaced the oil filter on gearbox and oil but it feels like it is in limp but its not no smells on oil gearbox doesn't Slip's gears it goes smooth but don't whant to shifted up i did had some scanners on its but it shows me po730 we clear it but it comes back what can be the problem
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Unfortunately I haven't had that problem before, but according to a national database of repair for the P0730 on your vehicle, if after replacing the filter you still get the same code, then the most likely cause of the problem is the transmission assembly.
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I did put aa launch scanner on today and it shows etc fault memory currently can that cause it
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