AutoCodes – Mercedes-Benz – P0240 Mercedes-Benz

P0240 Mercedes-Benz Code - Turbocharger/Supercharger Boost Sensor 'B' Circuit Range/Performance

Quick Answer

The boost pressure sensor responds to pressure changes in the intake manifold. Common causes include Boost pressure sensor harness is open or shorted, Boost pressure sensor circuit poor electrical connection, Faulty boost pressure sensor. 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: P0240 Mercedes-Benz indicates Turbocharger/Supercharger Boost Sensor 'B' Circuit Range/Performance.
Common causes: Common causes include Boost pressure sensor harness is open or shorted, Boost pressure sensor circuit poor electrical connection, Faulty boost pressure sensor.
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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 15,800

How popular is this code, among other codes? Low

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
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0240 Mercedes-Benz Description

The boost pressure sensor responds to pressure changes in the intake manifold. This pressure is created by the turbocharger and changes with accelerator pedal position (APP) and engine speed. The Engine Control Module (ECM) uses this information to assist in diagnosis of the barometric pressure (BARO) sensor and to provide engine overboost protection. The boost pressure sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The Engine Control Module (ECM) supplies 5 volts to the boost pressure sensor on the 5-volt reference 2 circuit, and provides a ground on a low reference circuit. The boost pressure sensor provides a signal to the ECM on a signal circuit relative to the pressure changes. The ECM monitors the boost pressure sensor signal for voltage outside of the normal range. The ECM calculates a predicted value for the boost pressure sensor. The ECM then compares the predicted value to the actual signal.

OBDII Code P0240 Mercedes-Benz - Turbocharger/Supercharger Boost Sensor 'B' Circuit Range/Performance - AutoCodes.com — P0240 Mercedes-Benz Code - Turbocharger/Supercharger Boost Sensor 'B' Circuit Range/Performance

What does this mean?

What are the Possible Causes of the DTC P0240 Mercedes-Benz?

Boost pressure sensor harness is open or shorted
Boost pressure sensor circuit poor electrical connection
Faulty boost pressure sensor
Faulty Turbo/Super Charger
Engine over temperature
Ignition misfire exceeds the calibrated threshold
Faulty Knock sensor (KS)

How to Fix the DTC P0240 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.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0240 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 P0240 Mercedes-Benz code?

Need more information on how to fix the P0240 Mercedes-Benz code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0240 Mercedes-Benz code diagnosed by a professional: Find a repair shop in your area

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 P0240 Mercedes-Benz Code

1. What are the common symptoms of OBDII code P0240 in a Mercedes-Benz related to the Turbocharger/Supercharger Boost Sensor 'B' Circuit Range/Performance?

- Common symptoms include reduced engine power, hesitation or lack of acceleration, rough idling, and the illumination of the Check Engine Light.

2. What are the possible causes of OBDII code P0240 in a Mercedes-Benz?

- The code P0240 can be triggered by issues such as a faulty turbocharger/supercharger boost sensor, wiring or connector problems, a vacuum leak in the intake system, or a malfunctioning turbocharger/supercharger itself.

3. How can I diagnose the cause of OBDII code P0240 in my Mercedes-Benz?

- Diagnosis involves checking the turbocharger/supercharger boost sensor, inspecting the wiring and connectors for any damage, conducting a vacuum leak test, and performing a thorough inspection of the turbocharger/supercharger components.

4. Can driving with OBDII code P0240 in a Mercedes-Benz cause further damage to the vehicle?

- It is recommended to address the issue promptly to avoid potential damage to the engine or turbocharger/supercharger components due to reduced performance and improper boost control.

5. What are some repair tips for resolving OBDII code P0240 in a Mercedes-Benz?

- Repair tips include replacing the turbocharger/supercharger boost sensor if faulty, repairing any damaged wiring or connectors, fixing vacuum leaks, and ensuring proper functioning of the turbocharger/supercharger system.

6. Is it safe to continue driving my Mercedes-Benz with OBDII code P0240 present?

- It is not advisable to drive the vehicle with the code P0240 active, as it can lead to decreased performance and potential long-term damage to engine components.

7. How much does it typically cost to repair OBDII code P0240 in a Mercedes-Benz?

- Repair costs can vary depending on the exact cause of the issue, but they may range from a few hundred to over a thousand dollars, including parts and labor.

8. Can I reset the Check Engine Light caused by OBDII code P0240 in my Mercedes-Benz on my own?

- Yes, you can reset the Check Engine Light using an OBDII scanner after addressing the underlying issue triggering code P0240. If the problem persists, the light may come back on.

9. How important is it to fix OBDII code P0240 in a Mercedes-Benz promptly?

- It is crucial to address code P0240 promptly to ensure optimal engine performance, prevent further damage, and maintain the overall health and longevity of the vehicle.

10. Are there any preventive maintenance steps I can take to avoid OBDII code P0240 in my Mercedes-Benz?

- Regularly servicing and maintaining the turbocharger/supercharger system, checking for leaks, using high-quality fuel, and addressing any warning signs promptly can help prevent the occurrence of code P0240.