ADAS Under The Hood: Blind Spot Monitoring (BSM) Systems and their Calibration Requirements

With nearly 300 million drivers in the US making countless lane changes daily, each one represents a potential blind spot incident that could lead to catastrophic consequences. While this vulnerability has existed since the dawn of automotive travel, technology has finally arrived to address it head-on.

Studies show properly functioning Blind Spot Monitoring systems reduce lane-change crashes by 14% and lane-change crashes with injuries by 23%. Yet many shops miss these critical calibrations due to the growing complexity of BSM systems.

The stakes are significant. Each blind spot-related accident averages $7,500, not including potential injuries or liability. For repair shops, this creates both risk and opportunity. With 73% of new vehicles offering BSM as standard or optional equipment in 2024. It's become one of the most common ADAS features you'll encounter.

But with every ADAS system loaded onto a vehicle as standard, there are just as many types of sensors and components that need to be calibrated in order to work properly. 

This guide breaks down everything you need to know about BSM systems: their operation, calibration requirements, and how to transform this knowledge into a profitable service offering.

Understanding Blind Spot Monitoring Systems

Blind Spot Monitoring does exactly what it sounds like it should: detect vehicles in places drivers can't easily see. 

The execution, however, is anything but. 

In order to do this task that our brains handle almost subconsciously, BSM systems require sophisticated networks of sensors, processors, and alert mechanisms working in concert to prevent one of driving's most common hazards.

Market analysts project the global BSM market to grow from $15.93 billion in 2024 to $24.1 billion by 2028, serving as a clear indicator that this technology has gone from luxury add-on to as standard as the seatbelt.

What’s also interesting to note: drivers like them. Consumer satisfaction rates for BSM hover around 84%, making these features one of the most appreciated among its ADAS cohorts. 

For repair shops, this means one thing: the demand for BSM-related calibration services will likely become an essential part of your business model.

How Blind Spot Monitoring Systems Work

Understanding how BSM systems function is crucial for ensuring their proper repair and calibration. 

The key components and their roles in keeping drivers safe usually include some combination of the following:

1. Radar Sensors - These are the most common detection methods for BSM systems. They can detect objects up to 10 meters away and do so effectively regardless of weather.

2. Ultrasonic Sensors - These are sometimes used in conjunction with radar systems. Since they’re particularly effective at lower speeds, they’re often doubling up with parking assistance systems. 

3. Camera Systems - onboard cameras are becoming increasingly common. They are often providing data to other ADAS features on board such as Forward Collision Warning or Autonomous Emergency Breaking (AEB).

Information from these sensors is often pulled together in a CPU that coordinates with vehicle's CAN bus system—meaning real time data can be passed to various ADAS systems quickly.

Alert Mechanisms

When a BSM system detects a vehicle or object, there are multiple types of warnings that can be used to let the driver know: 

• Visual Indicators - Color-coded lights flash yellow for detection and red for immediate danger. These will usually be LED lights installed in side mirrors. They may also be present in dashboard displays or heads-up displays (HUDs) in certain vehicles.
• Auditory Warnings - Similar to the color coding, these distinct warning tones will vary in volume or tone based on the threat level. 
• Haptic Feedback - these alerts include anything that physically signals to the driver that there is a risk. The steering wheel or seat might vibrate with varying intensity and is often combined with other alerts. Certain vehicles can also help guide the vehicle back on track.

Meanwhile, the Blind Spot Monitoring system is also talking to your turn signals to provide extra warnings during lane changes, work with lane departure systems to prevent side swipes, and even help your Lane Change Assistance system to prevent collisions. Research indicates that this type of approach to alerts significantly improves driver response time and system effectiveness. 

Critical Sensor Locations and Calibration Points

For effective BSM system repairs, you need to know exactly what those sensors are, where they live, and how they interact. Here's what makes this particularly challenging: sensor locations vary significantly by manufacturer, and even between different models from the same manufacturer.

Common Sensor Locations

The rear quarter panels house the primary BSM sensors in most vehicles. With how sensitive these components are, even minor body damage can affect sensor performance.

Bumper-mounted radar units, typically positioned behind the rear bumper cover, are also becoming increasingly common. Studies show that radar sensors account for about 60% of BSM systems, making these locations particularly important for collision repair shops.

Calibration Considerations

Each sensor location presents unique challenges:

• Quarter panel sensors must maintain specific angles relative to the vehicle's centerline
• Bumper-mounted sensors need exact height and angle measurements
• Cross-traffic detection systems often integrate multiple sensor points that must work in harmony

Here's what makes this critical for your shop: A sensor that's misaligned by just one degree can cause the same sort of blind spot they’re looking to account for which can be catastrophic at highway speeds.

So when do these systems need to be calibrated? 

Common Calibration Triggers for BSM

BSM calibration isn't only required due to obvious collision damage. There are many routine repairs and services that can affect these systems, often in ways that aren't immediately apparent.

Collision-Related Triggers

While quarter panel repairs are the most obvious culprits, bumper repairs or replacements, even when they seem minor, often necessitate BSM calibration. 

Why? 

Those radar sensors mounted behind your bumper covers need precise positioning to function correctly. 

Even removing and reinstalling the same bumper can throw off their alignment.

Non-Collision Triggers

Here's where it gets interesting. Many routine services can trigger the need for BSM calibration:

• Wheel alignments, particularly when adjusting rear toe angles
• Suspension work that affects vehicle ride height
• Paint work around sensor locations (yes, even paint thickness matters)
• Installing certain accessories, especially those near sensor locations

The Surprise Triggers

Some calibration requirements aren't obvious at all. For instance, vehicle manufacturers often require BSM calibration after:

• Software updates
• Tire size changes
• Even certain structural repairs that seem unrelated to BSM systems

The key takeaway? 

When in doubt, check the OEM specifications. Missing a required calibration isn't worth the risk to your customers or your business. If you’re not sure where to start, refer to our ADAS calibration checklist.

Calibration Workflow and Best Practices

A successful BSM calibration follows a structured workflow that leaves nothing to chance. Here's how to get it right every time.

Pre-Calibration Assessment 

Before touching any tools, conduct a thorough vehicle scan to establish a baseline and document all DTCs. Walk around the vehicle to verify all system components are properly connected and check for any physical damage near sensor areas. Ensure all software is current and review the specific OEM procedures for the vehicle you're working on—different manufacturers will almost always have unique requirements.

Environment Setup 

Your workspace needs careful preparation. Remove all metal objects and potential interference sources from the calibration area. Use proper equipment to verify the floor meets level specifications as even slight variations can affect calibration accuracy. Follow manufacturer guidelines for target placement, ensure proper lighting conditions, and confirm you have enough space around the vehicle for all necessary procedures.

Calibration Procedure 

Start by positioning the vehicle exactly as specified in OEM documentation. Once properly placed, connect your diagnostic tool and begin the calibration sequence. Follow each manufacturer-specific step precisely. Monitor system feedback throughout the process and address any error messages as they occur, not after completion.

Verification Process 

After calibration, perform a post-calibration scan and clear any DTCs. Take the vehicle for a road test under safe conditions to verify proper operation. Test all BSM functions and confirm proper integration with turn signals and other ADAS features. 

Should you still be having errors during the verification process, be sure to consider the following:

• Is your calibration area free of metal objects, other vehicles, and electronic equipment that could disrupt sensor communication? 
• Is there a dedicated calibration space with marked clearance zones?
• Have you verified all mounting brackets and body panels are within specification?
• Is your diagnostic equipment communicating properly with the vehicle? Check battery voltage, software versions, and ensure your calibration equipment is up to date.

Documentation 

Maintain detailed records of your work, including before and after scan results, environmental conditions during calibration, and all tools and equipment used. 

Document any error messages encountered and how they were resolved. Include comprehensive test drive results. This documentation protects both your shop and your customer.

Effortlessly handle identifying calibration requirements for Blind Spot Monitoring Systems

With the continued increase in ADAS systems listed as standard in vehicles, calibrating these systems is only going to get more commonplace. 

It won’t be long until it’s required for a shop to survive, nevermind grow. 

Fortunately, you won’t have to be stuck trawling through databases to find OEM requirements. Revv ADAS helps shops like yours streamline the calibration process:

• Instant identification of required calibrations
• Detailed OEM procedures at your fingertips
• Comprehensive documentation tools
• Integration with existing shop systems

Ready to transform your BSM calibration process? Set up a call with our team and see how Revv ADAS can help your shop capture more revenue while ensuring customer safety.