Mercedes Sprinter Blind Spot Assist Sensor Location Guide

1. Understanding Mercedes Sprinter Blind Spot Assist System

The Mercedes Sprinter Blind Spot Assist system enhances driving safety by monitoring areas beside and behind the vehicle. It alerts the driver to the presence of other vehicles or obstacles that may not be visible in the mirrors. This system significantly reduces the risk of accidents during lane changes or when merging onto highways.

• Function: To detect vehicles in the driver’s blind spots
• Coverage Area: Up to 10 feet behind and adjacent to the vehicle.
• Activation Speed: Active at speeds above 18 mph

1.1. How the System Works

The Blind Spot Assist system uses radar sensors, typically located in the rear bumper, to monitor the adjacent lanes. When a vehicle is detected in the blind spot, a visual warning appears in the corresponding side mirror. If the driver signals a lane change while a vehicle is present, the warning light flashes, and an audible alert may sound. Some advanced systems can even apply corrective steering to prevent a collision.

1.2. Benefits of Blind Spot Assist

• Enhanced Safety: Reduces the risk of accidents by alerting the driver to vehicles in blind spots.
• Increased Awareness: Provides an additional layer of awareness, especially useful in heavy traffic.
• Driver Confidence: Boosts driver confidence, particularly during lane changes and merging.
• Reduced Stress: Helps reduce the mental load on the driver by continuously monitoring blind spots.

1.3. Potential Limitations

Despite its benefits, the Blind Spot Assist system has limitations:

• Weather Conditions: Heavy rain, snow, or fog can affect sensor performance.
• Sensor Obstruction: Dirt, debris, or bumper damage can impair sensor function.
• System Malfunctions: Sensor or system failures can lead to false alerts or system deactivation.
• Reliance: Over-reliance on the system can reduce driver attentiveness.

2. Identifying the Location of Blind Spot Assist Sensors on a Mercedes Sprinter

Knowing the exact Mercedes Sprinter Blind Spot Assist Sensor Location is crucial for effective maintenance and repair. These sensors are typically installed within the rear bumper. Recognizing their placement can aid in diagnosing issues and ensuring their optimal performance.

2.1. Typical Sensor Locations

The sensors are generally located on the inner sides of the rear bumper, behind the bumper cover. The precise location can vary slightly depending on the model year and specific vehicle configuration.

• Rear Bumper: Inside the left and right sides.
• Sensor Orientation: Facing outward to monitor adjacent lanes.
• Mounting: Secured with brackets and screws to the bumper structure.

2.2. Visual Cues for Identifying Sensor Locations

While the sensors are hidden behind the bumper cover, there may be subtle visual cues indicating their presence. These include slight bulges or variations in the bumper’s surface.

• Bumper Surface: Look for slight protrusions or flat sections.
• Panel Gaps: Check for unusual gaps or seams in the bumper panels.
• Sensor Markings: Some bumpers may have small markings indicating sensor locations.

2.3. Using Vehicle Diagrams and Manuals

The most reliable way to pinpoint the exact sensor location is to consult the vehicle’s diagrams and service manuals. These resources provide detailed schematics and illustrations showing the precise placement of all components, including the Blind Spot Assist sensors.

• Service Manuals: Detailed diagrams and component locations.
• Online Databases: Vehicle-specific repair information and diagrams.
• Manufacturer Resources: Official Mercedes-Benz documentation.

2.4. Professional Diagnostic Tools

Professional diagnostic tools, such as those used at CARDIAGTECH.NET, can help identify the exact location and status of the Blind Spot Assist sensors. These tools can communicate with the vehicle’s onboard computer to provide real-time data and pinpoint any issues.

• Mercedes XENTRY: Official diagnostic software for Mercedes-Benz vehicles.
• OBD-II Scanners: Generic scanners that can read sensor data.
• Specialized Tools: Tools designed for advanced diagnostics and calibrations.

Rear blind spot assist sensors on a Mercedes-Benz module opened exposing internal corrosion

3. Step-by-Step Guide to Locating the Sensors

Finding the sensors involves careful inspection and, in some cases, removal of the bumper cover. Follow these steps to locate the sensors without causing damage to your vehicle.

3.1. Gather Necessary Tools

Before starting the process, gather the necessary tools. These typically include:

• Socket Set: Various sizes for removing bumper bolts.
• Screwdrivers: Both flathead and Phillips head.
• Trim Removal Tools: To safely remove plastic panels.
• Work Gloves: To protect your hands.
• Flashlight: For better visibility.

3.2. Prepare the Vehicle

Ensure the vehicle is safely parked on a level surface and the parking brake is engaged. Turn off the ignition and allow the vehicle to cool down.

• Safety First: Park on a level surface and engage the parking brake.
• Turn Off Ignition: Prevent electrical shorts or accidental activation of systems.
• Allow Cooling: Avoid burns from hot components.

3.3. Accessing the Rear Bumper

Accessing the sensors usually requires removing the rear bumper cover. This process varies slightly depending on the Sprinter model year but generally involves the following steps:

1. Locate Fasteners: Identify and remove all screws, bolts, and clips holding the bumper cover in place. These are typically found along the edges of the bumper, inside the wheel wells, and underneath the vehicle.
2. Remove Fasteners: Use the appropriate socket or screwdriver to remove the fasteners. Place them in a safe location to avoid losing them.
3. Detach Bumper Cover: Gently pull the bumper cover away from the vehicle. Start at one corner and work your way around, using trim removal tools to release any clips.
4. Disconnect Electrical Connectors: If there are any electrical connectors attached to the bumper cover (e.g., for parking sensors or license plate lights), disconnect them carefully.

3.4. Locating the Sensors Behind the Bumper

Once the bumper cover is removed, you should be able to see the Blind Spot Assist sensors mounted to the bumper structure.

• Identify Sensor Housings: Look for small, rectangular housings mounted on the inner sides of the bumper.
• Check Wiring: Inspect the wiring and connectors leading to the sensors for any signs of damage or corrosion.
• Note Sensor Position: Take note of the sensor’s orientation and mounting position for reinstallation.

3.5. Reassembling the Bumper

After inspecting or replacing the sensors, reassemble the bumper in the reverse order of disassembly:

1. Reconnect Electrical Connectors: Reattach any electrical connectors that were disconnected.
2. Align Bumper Cover: Align the bumper cover with the vehicle’s body.
3. Reattach Fasteners: Reinstall all screws, bolts, and clips to secure the bumper cover.
4. Ensure Proper Fit: Check that the bumper cover is properly aligned and securely attached.

4. Common Issues Affecting Blind Spot Assist Sensors

Several common issues can affect the performance of Blind Spot Assist sensors. Understanding these problems can help you diagnose and address them effectively.

4.1. Environmental Factors

Environmental conditions such as heavy rain, snow, and extreme temperatures can interfere with sensor operation. These factors can cause temporary or permanent sensor damage.

• Heavy Rain: Water can block sensor signals or infiltrate sensor housings.
• Snow and Ice: Ice buildup can obstruct sensor views and damage components.
• Extreme Temperatures: High heat can cause sensor malfunction, while cold can lead to brittle wiring.

4.2. Physical Damage

Physical damage from collisions, road debris, or improper handling can impair sensor function.

• Impact Damage: Accidents or impacts can misalign or break sensors.
• Road Debris: Stones and other debris can damage sensor surfaces.
• Improper Handling: Rough handling during maintenance can damage delicate components.

4.3. Electrical Problems

Electrical issues, such as wiring corrosion, loose connections, and blown fuses, can disrupt sensor operation.

• Wiring Corrosion: Exposure to moisture and salt can corrode wiring and connectors.
• Loose Connections: Vibrations can loosen electrical connections, causing intermittent issues.
• Blown Fuses: Overloads or shorts can blow fuses, disabling the system.

4.4. Software and Calibration Issues

Software glitches, outdated software, and improper calibration can affect sensor performance.

• Software Glitches: Bugs in the system software can cause malfunctions.
• Outdated Software: Old software versions may lack necessary updates and bug fixes.
• Improper Calibration: Sensors need to be properly calibrated to ensure accurate detection.

4.5. Diagnostic Trouble Codes (DTCs)

When the Blind Spot Assist system detects a problem, it stores Diagnostic Trouble Codes (DTCs) in the vehicle’s computer. These codes can be read using a diagnostic scanner to identify the specific issue.

• Reading DTCs: Use an OBD-II scanner to retrieve DTCs from the vehicle’s computer.
• Interpreting Codes: Consult a service manual or online database to interpret the meaning of each code.
• Troubleshooting: Follow the diagnostic procedures outlined in the service manual to troubleshoot the issue.

5. How to Test Mercedes Sprinter Blind Spot Assist Sensors

Testing the sensors is a crucial step in diagnosing and resolving issues. Here are methods to ensure they function correctly.

5.1. Visual Inspection

Begin with a visual inspection of the sensors and their surroundings. Look for any signs of damage, corrosion, or obstruction.

• Check Sensor Surface: Ensure the sensor surface is clean and free from debris.
• Inspect Wiring: Look for frayed, cracked, or corroded wiring.
• Examine Connectors: Make sure connectors are securely attached and free from corrosion.

5.2. Using a Multimeter

A multimeter can be used to check the electrical continuity and voltage of the sensor wiring.

1. Disconnect Sensor: Disconnect the sensor from the wiring harness.
2. Check Continuity: Use the multimeter to check the continuity of the wiring between the sensor connector and the vehicle’s computer.
3. Measure Voltage: With the ignition on, measure the voltage at the sensor connector to ensure it is receiving power.

5.3. Using Diagnostic Scan Tools

Diagnostic scan tools, such as the Mercedes XENTRY system, can provide real-time data from the sensors and perform diagnostic tests.

1. Connect Scanner: Connect the diagnostic scanner to the vehicle’s OBD-II port.
2. Access Blind Spot Assist System: Navigate to the Blind Spot Assist system in the scanner’s menu.
3. Read Sensor Data: View real-time data from the sensors, such as signal strength and sensor status.
4. Perform Diagnostic Tests: Run diagnostic tests to check sensor functionality and identify any faults.

5.4. Simulating Blind Spot Conditions

You can simulate blind spot conditions to test the sensor’s response.

1. Park Vehicle: Park the vehicle in a safe location with enough space around it.
2. Place Obstacle: Place a large object (e.g., a cardboard box or another vehicle) in the blind spot area.
3. Monitor System Response: Observe the Blind Spot Assist system’s response. The warning light should illuminate in the corresponding side mirror.
4. Test with Signal: Activate the turn signal on the side with the obstacle. The warning light should flash, and an audible alert may sound.

5.5. Road Test

A road test can help verify the sensor’s performance under real-world driving conditions.

1. Drive Vehicle: Drive the vehicle on a road with moderate traffic.
2. Monitor System: Observe the Blind Spot Assist system’s performance. Ensure the warning lights illuminate when vehicles enter the blind spot.
3. Perform Lane Changes: Perform lane changes to test the system’s response. The warning lights should flash, and an audible alert may sound if a vehicle is present in the blind spot.

6. Mercedes Sprinter Blind Spot Assist Sensor Replacement Guide

Replacing a faulty sensor involves removing the old unit and installing a new one. Here’s a guide.

6.1. Preparing for Replacement

Before starting the replacement process, gather the necessary tools and parts.

• New Sensor: Purchase a replacement sensor that is compatible with your Sprinter model.
• Tools: Gather the tools needed for removing the bumper cover and sensor (see Section 3.1).
• Safety Gear: Wear safety glasses and gloves to protect yourself.

6.2. Removing the Old Sensor

1. Access Sensor: Remove the rear bumper cover to access the sensor (see Section 3.3).
2. Disconnect Electrical Connector: Disconnect the electrical connector from the sensor.
3. Remove Mounting Hardware: Remove the screws or bolts holding the sensor in place.
4. Remove Sensor: Carefully remove the old sensor from its mounting bracket.

6.3. Installing the New Sensor

1. Position Sensor: Place the new sensor in the mounting bracket, ensuring it is properly aligned.
2. Attach Mounting Hardware: Reinstall the screws or bolts to secure the sensor.
3. Reconnect Electrical Connector: Reconnect the electrical connector to the sensor.
4. Verify Installation: Ensure the sensor is securely mounted and the electrical connector is properly attached.

6.4. Reassembling the Bumper

Reassemble the bumper in the reverse order of disassembly (see Section 3.5).

1. Align Bumper Cover: Align the bumper cover with the vehicle’s body.
2. Reattach Fasteners: Reinstall all screws, bolts, and clips to secure the bumper cover.
3. Ensure Proper Fit: Check that the bumper cover is properly aligned and securely attached.

6.5. Calibration and Testing

After replacing the sensor, it is essential to calibrate the system and verify its performance.

1. Calibration: Use a diagnostic scan tool to calibrate the Blind Spot Assist system. Follow the manufacturer’s instructions for calibration.
2. Testing: Perform the tests outlined in Section 5 to verify that the new sensor is functioning correctly.

7. Maintenance Tips for Mercedes Sprinter Blind Spot Assist System

Regular maintenance can help prevent issues and ensure the system operates effectively.

7.1. Regular Cleaning

Keep the sensor surfaces clean and free from dirt, debris, and ice.

• Wash Regularly: Wash the vehicle regularly to remove dirt and grime.
• Clean Sensors: Use a soft cloth and mild cleaner to clean the sensor surfaces.
• Remove Ice and Snow: Clear ice and snow from the sensors during winter.

7.2. Inspect Wiring and Connectors

Periodically inspect the wiring and connectors for signs of damage or corrosion.

• Check Wiring: Look for frayed, cracked, or corroded wiring.
• Secure Connectors: Ensure connectors are securely attached and free from corrosion.
• Apply Dielectric Grease: Apply dielectric grease to the connectors to prevent corrosion.

7.3. Check Bumper Alignment

Ensure the rear bumper is properly aligned and free from damage.

• Inspect Bumper: Look for signs of misalignment, cracks, or dents.
• Repair Damage: Repair any damage to the bumper to prevent sensor misalignment.
• Professional Inspection: Have the bumper alignment checked by a professional during routine maintenance.

7.4. Software Updates

Keep the system software up to date to ensure optimal performance and compatibility.

• Check for Updates: Check for software updates during routine maintenance.
• Install Updates: Install any available updates to improve system performance and fix bugs.
• Professional Service: Have software updates performed by a qualified technician.

7.5. Professional Inspections

Regular professional inspections can help identify potential issues before they become major problems.

• Routine Maintenance: Include Blind Spot Assist system inspection as part of routine maintenance.
• Diagnostic Scan: Have a diagnostic scan performed to check for DTCs and system faults.
• Expert Advice: Seek advice from a qualified technician on maintenance and troubleshooting.

Side radar sensor on a Mercedes-Benz vehicle

8. Benefits of Using OEM Parts for Replacement

When replacing Blind Spot Assist sensors, using Original Equipment Manufacturer (OEM) parts offers several advantages.

8.1. Guaranteed Compatibility

OEM parts are designed specifically for your vehicle, ensuring perfect compatibility and fit.

• Exact Fit: OEM parts are made to the exact specifications of the original components.
• No Modifications: OEM parts require no modifications for installation.
• Seamless Integration: OEM parts integrate seamlessly with the vehicle’s systems.

8.2. Superior Quality

OEM parts are manufactured to high-quality standards, ensuring reliability and longevity.

• Durable Materials: OEM parts are made from durable materials that withstand harsh conditions.
• Rigorous Testing: OEM parts undergo rigorous testing to ensure performance and reliability.
• Long Lifespan: OEM parts are designed to last, reducing the need for frequent replacements.

8.3. Optimal Performance

OEM parts are designed to deliver optimal performance, ensuring the Blind Spot Assist system functions as intended.

• Accurate Detection: OEM sensors provide accurate and reliable detection of vehicles in the blind spot.
• Quick Response: OEM sensors respond quickly to changes in the driving environment.
• Consistent Performance: OEM sensors provide consistent performance over time.

8.4. Warranty Coverage

OEM parts typically come with a warranty, providing added peace of mind.

• Manufacturer Warranty: OEM parts are backed by the manufacturer’s warranty.
• Coverage for Defects: The warranty covers defects in materials and workmanship.
• Protection Against Failure: The warranty protects against premature failure of the part.

8.5. Maintaining Vehicle Value

Using OEM parts can help maintain the vehicle’s value.

• Preserving Original Condition: OEM parts help preserve the original condition of the vehicle.
• Ensuring Reliability: OEM parts ensure the vehicle remains reliable and safe.
• Increasing Resale Value: Using OEM parts can increase the vehicle’s resale value.

9. Troubleshooting Guide for Common Issues

This guide provides solutions to common issues that may arise with the Blind Spot Assist system.

9.1. System Not Activating

If the system is not activating, check the following:

1. Check Power: Ensure the system is receiving power by checking the fuse and wiring.
2. Verify Speed: Confirm the vehicle is traveling above the activation speed (18 mph).
3. Inspect Sensors: Check the sensors for damage, obstruction, or misalignment.
4. Diagnostic Scan: Perform a diagnostic scan to check for DTCs.

9.2. False Alarms

If the system is producing false alarms, check the following:

1. Clean Sensors: Ensure the sensors are clean and free from debris.
2. Check Alignment: Verify the sensors are properly aligned.
3. Software Update: Check for and install any available software updates.
4. Recalibration: Recalibrate the system using a diagnostic scan tool.

9.3. Intermittent Operation

If the system is operating intermittently, check the following:

1. Wiring Connections: Inspect the wiring connections for looseness or corrosion.
2. Sensor Condition: Check the sensors for damage or wear.
3. Diagnostic Scan: Perform a diagnostic scan to check for intermittent faults.
4. Environmental Factors: Consider whether environmental conditions (e.g., rain, snow) are affecting performance.

9.4. Warning Light On Dashboard

If the warning light is illuminated on the dashboard, check the following:

1. Diagnostic Scan: Perform a diagnostic scan to retrieve DTCs.
2. Troubleshoot DTCs: Follow the diagnostic procedures outlined in the service manual to troubleshoot the DTCs.
3. Repair Faults: Repair any faults identified during the troubleshooting process.
4. Clear DTCs: Clear the DTCs after the faults have been repaired.

9.5. System Deactivated Message

If the system displays a “System Deactivated” message, check the following:

1. Diagnostic Scan: Perform a diagnostic scan to retrieve DTCs.
2. Troubleshoot DTCs: Follow the diagnostic procedures outlined in the service manual to troubleshoot the DTCs.
3. Repair Faults: Repair any faults identified during the troubleshooting process.
4. Reset System: Reset the system using a diagnostic scan tool.

10. Importance of Professional Assistance

While some maintenance and troubleshooting tasks can be performed by vehicle owners, professional assistance is crucial for complex issues.

10.1. Expertise and Experience

Professional technicians have the expertise and experience needed to diagnose and repair complex issues accurately.

• Training: Technicians undergo extensive training to understand vehicle systems and diagnostic procedures.
• Experience: Technicians have experience working on a wide range of vehicles and systems.
• Problem-Solving Skills: Technicians have developed problem-solving skills through years of experience.

10.2. Specialized Tools and Equipment

Professional technicians have access to specialized tools and equipment needed to perform complex repairs.

• Diagnostic Scanners: Technicians use advanced diagnostic scanners to retrieve DTCs and perform system tests.
• Calibration Tools: Technicians use specialized calibration tools to ensure sensors are properly calibrated.
• Repair Equipment: Technicians have access to a wide range of repair equipment to perform necessary repairs.

10.3. Accurate Diagnosis

Professional technicians can accurately diagnose issues, saving time and money in the long run.

• System Knowledge: Technicians have a deep understanding of vehicle systems.
• Diagnostic Procedures: Technicians follow established diagnostic procedures to identify faults.
• Data Analysis: Technicians analyze data from diagnostic scans to pinpoint the root cause of issues.

10.4. Proper Repairs

Professional technicians perform repairs correctly, ensuring the system functions as intended.

• Quality Parts: Technicians use high-quality parts for repairs.
• Correct Procedures: Technicians follow correct repair procedures to ensure the repair is done properly.
• Testing and Verification: Technicians test and verify the repair to ensure the system is functioning correctly.

10.5. Warranty Protection

Professional repairs often come with a warranty, providing added peace of mind.

• Coverage for Repairs: The warranty covers the repair work performed by the technician.
• Protection Against Faults: The warranty protects against faults that may arise after the repair.
• Peace of Mind: The warranty provides peace of mind knowing that the repair is covered.

11. Cost Considerations for Sensor Replacement

Understanding the costs associated with sensor replacement can help you budget for repairs.

11.1. Part Costs

The cost of replacement sensors can vary depending on the manufacturer and supplier.

• OEM Sensors: OEM sensors are typically more expensive than aftermarket options.
• Aftermarket Sensors: Aftermarket sensors can be more affordable but may not offer the same level of quality and reliability.
• Online Retailers: Online retailers may offer competitive prices on replacement sensors.

11.2. Labor Costs

Labor costs can vary depending on the repair shop and the complexity of the repair.

• Hourly Rate: Repair shops typically charge an hourly rate for labor.
• Estimated Time: The estimated time for sensor replacement can vary depending on the vehicle and the shop’s experience.
• Additional Services: Additional services, such as calibration and diagnostic scans, may add to the labor costs.

11.3. Diagnostic Costs

Diagnostic costs may be incurred if the repair shop needs to perform diagnostic tests to identify the issue.

• Diagnostic Fee: Repair shops may charge a diagnostic fee for performing diagnostic tests.
• Scan Tools: The cost of using diagnostic scan tools may be included in the diagnostic fee.
• Troubleshooting Time: The time spent troubleshooting the issue may add to the diagnostic costs.

11.4. Calibration Costs

Calibration costs may be incurred if the system needs to be calibrated after sensor replacement.

• Calibration Fee: Repair shops may charge a calibration fee for calibrating the system.
• Calibration Tools: The cost of using calibration tools may be included in the calibration fee.
• Software Updates: Software updates may be required during calibration, adding to the costs.

11.5. Total Cost Estimate

The total cost of sensor replacement can include part costs, labor costs, diagnostic costs, and calibration costs.

• Obtain Estimates: Obtain estimates from multiple repair shops to compare prices.
• Consider Quality: Consider the quality of the parts and the expertise of the technicians when comparing estimates.
• Factor in Warranty: Factor in the warranty coverage offered by the repair shop when making a decision.

12. Future Trends in Blind Spot Assist Technology

Blind Spot Assist technology is continuously evolving, with new features and advancements on the horizon.

12.1. Enhanced Sensor Technology

Future systems may use more advanced sensor technology, such as higher-resolution radar and lidar, to improve detection accuracy and range.

• Higher Resolution: Higher-resolution sensors can provide more detailed information about the surrounding environment.
• Lidar Integration: Lidar (Light Detection and Ranging) can provide accurate distance measurements, improving detection accuracy.
• Extended Range: Sensors with extended range can detect vehicles and objects further away, providing more time to react.

12.2. Integration with Other Safety Systems

Future systems may be more closely integrated with other safety systems, such as lane-keeping assist and adaptive cruise control, to provide a more comprehensive safety net.

• Lane-Keeping Assist: Integration with lane-keeping assist can help prevent unintentional lane departures.
• Adaptive Cruise Control: Integration with adaptive cruise control can help maintain a safe following distance.
• Automated Emergency Braking: Integration with automated emergency braking can help prevent collisions.

12.3. Artificial Intelligence (AI)

AI can be used to analyze sensor data and make more intelligent decisions, improving the system’s overall performance.

• Object Recognition: AI can be used to recognize different types of objects, such as cars, trucks, and motorcycles.
• Predictive Algorithms: AI can be used to predict the behavior of other vehicles and pedestrians.
• Adaptive Learning: AI can be used to adapt the system’s performance to different driving conditions and environments.

12.4. Over-the-Air (OTA) Updates

Future systems may support Over-the-Air (OTA) updates, allowing manufacturers to push software updates and improvements to vehicles remotely.

• Remote Updates: OTA updates can be installed without requiring a visit to a repair shop.
• Software Improvements: OTA updates can include software improvements, bug fixes, and new features.
• Convenience: OTA updates provide convenience for vehicle owners, eliminating the need for manual updates.

12.5. Enhanced User Interface (UI)

Future systems may feature enhanced user interfaces that provide more intuitive and informative feedback to the driver.

• Visual Displays: Enhanced visual displays can provide clear and concise information about the system’s status.
• Audible Alerts: Enhanced audible alerts can provide timely warnings about potential hazards.
• Customizable Settings: Customizable settings can allow drivers to adjust the system’s behavior to their preferences.