Automotive Cybersecurity for ECUs & In-Vehicle Networks

Introduction

As vehicles become increasingly connected and software-driven, automotive cybersecurity has emerged as a critical priority. Modern cars contain over 100 Electronic Control Units (ECUs) and rely on complex in-vehicle networks such as CAN Bus and Automotive Ethernet to manage everything from braking and steering to infotainment and telematics. This digital transformation, while enabling innovation, exposes vehicles to new and evolving cybersecurity threats.

With the rise of connected vehicles, over-the-air (OTA) updates, and Vehicle-to-Everything (V2X) communication, the attack surface has expanded exponentially. Hackers can exploit vulnerabilities in ECUs, compromise in-vehicle network security, or even hijack vehicles remotely. To address these risks, automotive OEMs and suppliers must implement robust cybersecurity for ECUs, adhere to ISO/SAE 21434 compliance, and integrate security throughout the automotive cybersecurity lifecycle.

This article explores the common threats, regulatory requirements, and best practices for securing ECUs and in-vehicle networks, laying the foundation for safer, more resilient vehicles in the age of smart mobility.

What is Automotive Cybersecurity?

Automotive cybersecurity refers to the protection of vehicle systems, Electronic Control Units (ECUs), and in-vehicle networks from cyber threats that can compromise safety, functionality, and data privacy. It involves the implementation of security measures across the automotive software, hardware, and communication layers to prevent unauthorized access, manipulation, or data breaches in modern vehicles.

Importance of Automotive Cybersecurity in Modern Vehicles

As vehicles evolve into connected platforms with real-time communication capabilities, vehicle cybersecurity has become a mission-critical focus. Advanced features like ADAS, infotainment systems, remote diagnostics, and over-the-air (OTA) updates introduce significant vulnerabilities. Without robust ECU cybersecurity and in-vehicle network security, malicious actors could exploit these technologies, putting both passengers and public safety at risk.

Key risks include:

• Remote control of vehicle functions (e.g., braking or steering)
• Data theft from onboard systems
• Disruption of vehicle-to-everything (V2X) communication
• Spread of malware across the CAN Bus and other networks

Evolution of Vehicle Cybersecurity Threats

The evolution of automotive cybersecurity threats parallels the industry’s digital transformation. Early vehicles were largely isolated systems with minimal cyber exposure. Today’s software-defined vehicles rely on complex codebases, wireless connectivity, and cloud integration, creating multiple attack vectors.

Major developments include:

• Introduction of CAN Bus vulnerabilities
• Rise of connected and autonomous vehicles (CAVs)
• Emergence of OTA updates and telematics platforms
• Growing sophistication of automotive hacking techniques
• Regulatory push for ISO/SAE 21434 and UNECE WP.29 compliance

What is Connected Vehicles, ECUs, and In-Vehicle Network Security?

Connected vehicles are equipped with dozens of ECUs, each responsible for specific vehicle functions like engine control, braking, climate management, and communication. These ECUs interact via in-vehicle networks such as:

• Controller Area Network (CAN Bus)
• Automotive Ethernet
• LIN and FlexRay

These systems enable fast data exchange but are inherently vulnerable if not secured. In-vehicle network security ensures the integrity, confidentiality, and authenticity of data traveling across these communication channels. As threats increase, automakers are prioritizing real-time intrusion detection systems (IDS) and secure ECU architectures to protect both the vehicle and its occupants.

Understanding ECUs and In-Vehicle Networks

What are Electronic Control Units (ECUs) in Automotive Systems?

Electronic Control Units (ECUs) are embedded systems that manage specific functions within a vehicle. Modern cars can contain between 70 and over 100 ECUs, each responsible for operations such as engine control, braking, power steering, infotainment, and advanced driver assistance systems (ADAS). These units process real-time data from various sensors and actuators to ensure seamless vehicle operation.

ECU cybersecurity is crucial because compromised ECUs can lead to severe safety failures, unauthorized access, and system-wide vulnerabilities. As vehicles become more software-driven and connected, securing each ECU has become a core aspect of automotive cybersecurity.

Role of In-Vehicle Networks in Vehicle Functionality

To coordinate the functions of multiple ECUs, modern vehicles rely on complex in-vehicle networks. These communication networks transmit data among ECUs, sensors, and controllers, enabling real-time responses and automation across various vehicle domains.

Without robust in-vehicle network security, a single point of failure or attack can cascade across multiple ECUs. Cyber attackers can exploit network weaknesses to send malicious commands, intercept sensitive data, or disable critical safety systems.

Common In-Vehicle Communication Protocols

Several specialized communication protocols are used to manage data flow between ECUs in different automotive domains. The most common in-vehicle network protocols include:

Controller Area Network (CAN Bus)

• Widely used in automotive systems for real-time control
• Lightweight and efficient, but has known vulnerabilities
• Lacks built-in encryption or authentication mechanisms

Automotive Ethernet

• High-speed communication protocol used in advanced applications
• Supports infotainment, ADAS, and high-bandwidth data transmission
• Emerging as the backbone for software-defined vehicles

Local Interconnect Network (LIN)

• Low-cost, low-speed protocol for simple sensor-to-ECU communications
• Common in body electronics like mirrors, windows, and lighting

FlexRay

• High-speed, time-deterministic protocol
• Often used in safety-critical systems such as braking and steering
• Offers better fault tolerance than CAN Bus or LIN

As vehicles evolve, the combination of ECUs and high-performance in-vehicle networks requires layered automotive cybersecurity strategies. Ensuring secure communication protocols, real-time monitoring, and network segmentation is vital for protecting the modern vehicle ecosystem.

Common Cyber Threats Targeting ECUs & In-Vehicle Networks

As vehicles become more software-reliant and connected, cybersecurity threats targeting ECUs and in-vehicle networks have grown in both frequency and sophistication. These threats pose serious risks to safety, privacy, and overall vehicle integrity, making automotive cybersecurity a critical area of concern for OEMs and Tier-1 suppliers alike.

Top Cybersecurity Threats for ECUs

Electronic Control Units (ECUs) are susceptible to a range of cyberattacks due to their lack of built-in security features, limited processing power, and growing interconnectivity. Common threats include:

• Unauthorized access to ECUs via diagnostic ports (OBD-II)
• Firmware tampering to alter vehicle behavior
• Malware injection during software updates
• Spoofing or replay attacks to simulate legitimate ECU messages
• Remote control of safety-critical functions (e.g., braking or acceleration)

CAN Bus Vulnerabilities and Exploitation Examples

The Controller Area Network (CAN Bus), one of the most widely used in-vehicle communication protocols, lacks essential security mechanisms such as encryption and message authentication. As a result, it’s a prime target for attackers.

Key vulnerabilities include:

• Message injection: Malicious actors can spoof messages to control ECUs
• Bus flooding: Overwhelms the network, causing a denial-of-service (DoS)
• Eavesdropping: Intercepting unencrypted data across the CAN network

Example: In the well-known Jeep Cherokee hack (2015), researchers remotely accessed the CAN Bus via the infotainment system and took control of the steering, brakes, and transmission.

Risks in Infotainment Systems, OTA Updates, and V2X Communication

Infotainment Systems

• Often connected to external devices and the internet
• Serve as entry points to deeper vehicle networks
• Vulnerable to malicious apps, Bluetooth exploits, and USB-based attacks

Over-the-Air (OTA) Updates

• Allow remote firmware and software updates
• Pose a risk if updates are not properly authenticated and encrypted
• Attackers can inject malicious code during update transmissions

Vehicle-to-Everything (V2X) Communication

• Enables communication between vehicles, infrastructure, and pedestrians
• Opens doors to man-in-the-middle attacks, data spoofing, and privacy breaches
• Requires strong cryptographic protections to ensure authenticity and confidentiality

These incidents underscore the urgent need for real-time intrusion detection, secure ECU firmware, and end-to-end network security in all vehicle architectures.

Key Challenges Automotive Cybersecurity Systems

Implementing robust automotive cybersecurity in modern vehicles is complex and multi-dimensional. As the industry shifts toward connected, software-defined vehicles, automakers face increasing challenges in securing ECUs, in-vehicle networks, and digital ecosystems while maintaining performance, safety, and compliance.

Complexity of Embedded System Security

Embedded systems in vehicles are highly specialized, with tightly constrained memory, power, and processing capacity. These limitations make it difficult to integrate conventional cybersecurity measures such as encryption, firewalls, or intrusion detection directly into ECUs without impacting system performance or reliability.

Key issues include:

• Fragmented architecture across dozens of ECUs
• Vendor-specific firmware and protocols
• Inconsistent security policies across domains (powertrain, infotainment, etc.)

Addressing embedded system security requires tailored, lightweight cybersecurity solutions designed specifically for automotive applications.

Balancing Functional Safety vs. Cybersecurity

In the automotive domain, functional safety (as defined by standards like ISO 26262) ensures that a system operates correctly even in the event of a fault. However, cybersecurity introduces external threats that are not addressed by traditional safety approaches.

The challenge lies in balancing these priorities:

• Safety mechanisms must function even if under a cyberattack
• Cybersecurity measures must not interfere with safety-critical responses
• Both domains must work cohesively without creating new risks

This intersection is a core focus of ISO/SAE 21434, which mandates integrating cybersecurity across the vehicle lifecycle alongside safety assurance.

Limited Resources in ECUs for Real-Time Protection

Most ECUs are not built with high-performance processors or excess memory, which limits their ability to run real-time cybersecurity functions like anomaly detection, behavior analysis, or cryptographic operations.

Consequences include:

• Delayed threat detection or response
• Inability to patch vulnerabilities remotely
• Greater reliance on external systems for cybersecurity monitoring

To mitigate this, automakers must implement efficient, resource-aware cybersecurity solutions that don’t compromise performance or safety.

Increasing Attack Surfaces in Software-Defined Vehicles

The shift toward software-defined vehicles (SDVs) introduces a broader attack surface, as more vehicle functions are controlled by software and remotely updatable systems. Connectivity through OTA updates, cloud integration, telematics, and V2X communication expands potential entry points for attackers.

Emerging risks include:

• Lateral movement across ECUs via in-vehicle networks
• Exploits through third-party applications or mobile APIs
• Dependency on secure software development and update practices

Addressing these threats requires a holistic cybersecurity architecture that spans from the ECU level to the cloud, covering all phases of the automotive cybersecurity lifecycle.

ISO/SAE 21434 & Regulatory Compliance

ISO/SAE 21434 is the globally recognized standard that defines automotive cybersecurity requirements across the vehicle lifecycle. Developed jointly by the International Organization for Standardization (ISO) and SAE International, this standard addresses the cybersecurity risks in road vehicles, including components, ECUs, in-vehicle networks, and external interfaces.

It establishes a structured framework for:

• Risk assessment and threat modeling
• Cybersecurity management systems (CSMS)
• Security validation and verification
• Incident response and post-production monitoring

Compliance with ISO/SAE 21434 is not only essential for automotive cybersecurity assurance but also increasingly mandated under global regulations like UNECE WP.29 for type approval of connected vehicles.

Role of Standards in Automotive Cybersecurity Lifecycle Management

Standards like ISO/SAE 21434 play a central role in managing cybersecurity throughout the automotive cybersecurity lifecycle, from concept and development to production and decommissioning.

They help ensure:

• Security-by-design principles are adopted during ECU and network development
• Cybersecurity risk assessments are embedded in product planning
• Traceability of cybersecurity requirements across hardware, software, and communication layers
• Ongoing monitoring and threat mitigation post-deployment

By aligning development with ISO/SAE 21434, OEMs and Tier-1 suppliers can ensure systematic, auditable, and repeatable security practices across the supply chain.

How to Implement Compliance Across ECUs and In-Vehicle Networks

To achieve ISO/SAE 21434 compliance across ECUs and in-vehicle networks, organizations should follow a structured implementation approach:

1. Establish a Cybersecurity Management System (CSMS)

• Define governance, roles, and responsibilities for cybersecurity
• Integrate cybersecurity into existing quality and safety processes

2. Perform Threat Analysis and Risk Assessment (TARA)

• Identify assets (e.g., ECUs, sensors, networks)
• Analyze potential threats and attack paths
• Evaluate risk severity and assign mitigation strategies

3. Define Cybersecurity Goals and Requirements

• Apply security-by-design across embedded software and hardware
• Enforce encryption, authentication, and secure boot mechanisms in ECUs
• Implement secure communication protocols across CAN Bus, Ethernet, etc.

4. Validate and Verify Cybersecurity Measures

• Conduct penetration testing, fuzz testing, and vulnerability scans
• Ensure requirements traceability and test coverage using lifecycle tools

5. Monitor and Update Post-Production

• Deploy OTA update mechanisms with secure channels
• Continuously monitor for new vulnerabilities and respond to incidents
• Maintain a cybersecurity incident response plan

Achieving and maintaining ISO/SAE 21434 compliance not only supports regulatory approval but also strengthens the overall automotive cybersecurity posture, building trust in connected and autonomous vehicles.

Best Practices for Securing ECUs & In-Vehicle Networks

With the rise of connected, software-defined vehicles, the attack surface across ECUs and in-vehicle networks has expanded dramatically. To ensure robust automotive cybersecurity, automakers and suppliers must implement best practices that go beyond basic security checks, addressing both preventive and responsive strategies across the vehicle cybersecurity lifecycle.

Secure Boot, Firmware Protection, and Encryption

Implementing secure boot ensures that only trusted and verified software can run on the ECU during startup. This prevents unauthorized firmware from being loaded and executed.

Best practices include:

• Code signing for firmware using cryptographic keys
• Runtime integrity checks to detect tampering
• Flash memory protection to prevent reverse engineering
• End-to-end encryption of in-vehicle network communications to maintain confidentiality and integrity

These measures form the first line of defense against ECU compromise and malware injection.

Intrusion Detection Systems (IDS) and Penetration Testing

Deploying Intrusion Detection Systems (IDS) enables real-time monitoring of in-vehicle network traffic for anomalies or unauthorized activity. IDS solutions can be:

• Signature-based, detecting known attack patterns
• Anomaly-based, identifying deviations from normal behavior

In parallel, penetration testing is essential to evaluate system robustness by simulating real-world cyberattacks. Testing should cover:

• ECUs
• CAN Bus and Ethernet traffic
• Telematics and infotainment interfaces
• Third-party integrations and cloud services

Combined, IDS and penetration testing support both proactive threat prevention and regulatory compliance with standards like ISO/SAE 21434.

Over-the-Air (OTA) Update Security and Patch Management

OTA capabilities offer convenience, but without proper protection, they introduce critical vulnerabilities. Best practices include:

• Encrypted update packages and secure transmission channels
• Firmware authenticity validation via digital signatures
• Fail-safe mechanisms to roll back updates if errors occur
• Patch management policies to ensure timely vulnerability remediation

A secure OTA process enables continuous cybersecurity maintenance across the vehicle’s lifecycle.

Designing an Automotive Cybersecurity Architecture for Connected Vehicles

Building a resilient cybersecurity architecture for connected vehicles requires a defense-in-depth approach:

• Segment vehicle networks to isolate critical ECUs from less-trusted domains (e.g., infotainment)
• Use secure gateways and firewalls to manage cross-domain communication
• Implement access control policies for internal and external connections
• Integrate hardware security modules (HSMs) to safeguard encryption keys and credentials

This layered security architecture minimizes the risk of lateral attacks and ensures system-wide protection.

Real-Time ECU Protection and Anomaly Detection Techniques

To effectively secure ECUs during operation, implement real-time protection and anomaly detection strategies:

• ECU self-diagnostics and health monitoring
• Behavioral baselining to detect unauthorized deviations
• Event logging for forensic analysis and compliance audits
• Automated threat response, such as isolating compromised ECUs or disabling specific functions

These techniques enhance the vehicle’s ability to detect, respond to, and recover from cyber threats without manual intervention.

Together, these best practices form a comprehensive strategy for automotive cybersecurity, safeguarding ECUs, in-vehicle networks, and connected vehicle ecosystems from evolving threats.

Automotive Cybersecurity Testing and Risk Assessment

Ensuring automotive cybersecurity requires not only preventive controls but also continuous evaluation of system vulnerabilities. Effective cybersecurity testing and risk assessment help identify, prioritize, and mitigate threats to Electronic Control Units (ECUs) and in-vehicle networks, especially in today’s highly connected and software-intensive vehicles.

Importance of Automotive Cybersecurity Risk Assessment

Cybersecurity risk assessment is the foundation of any secure vehicle development strategy. It allows manufacturers to:

• Identify critical assets such as ECUs, gateways, and V2X interfaces
• Analyze potential attack paths across in-vehicle networks
• Evaluate impact and likelihood of threats
• Prioritize risk mitigation strategies based on severity

Risk assessments should be performed regularly throughout the automotive cybersecurity lifecycle to keep pace with evolving threats and system updates.

Tools and Techniques for Automotive Cybersecurity Testing

Various cybersecurity testing tools and techniques are used to validate the resilience of automotive systems, including:

• Static Application Security Testing (SAST) for embedded code analysis
• Dynamic Application Security Testing (DAST) to evaluate real-time behavior
• Fuzz testing to identify buffer overflows or unexpected inputs in ECUs
• Vulnerability scanning tools for network and firmware-level weaknesses
• Hardware-in-the-loop (HIL) simulation for realistic test environments

These techniques allow engineers to uncover vulnerabilities early and improve security posture proactively.

Using Penetration Testing and Threat Modeling to Harden Systems

Penetration testing simulates real-world cyberattacks to uncover exploitable vulnerabilities in ECUs, telematics units, infotainment systems, and OTA infrastructure. It validates the effectiveness of implemented security controls and identifies hidden risks.

Threat modeling (such as TARA, Threat Analysis and Risk Assessment) complements penetration testing by:

• Systematically mapping vehicle components, data flows, and interfaces
• Identifying potential adversaries and their capabilities
• Estimating potential damage and developing mitigation strategies

Together, these methods help harden vehicle systems against both known and emerging cyber threats.

Integrating Security into the Vehicle Development Lifecycle

To build secure vehicles from the ground up, cybersecurity must be integrated into every phase of the automotive development lifecycle:

1. Concept & Requirements Phase
   • Define cybersecurity goals and risk tolerance
   • Identify critical assets and attack surfaces
2. Design & Architecture Phase
   • Apply security-by-design principles
   • Use secure protocols across CAN Bus, Ethernet, and LIN
3. Implementation Phase
   • Validate firmware integrity
   • Use secure coding practices and cryptographic protection
4. Testing & Validation Phase
   • Perform penetration testing and static/dynamic analysis
   • Validate threat mitigations through simulation
5. Production & Post-Production Phase
   • Monitor for new vulnerabilities
   • Enable OTA updates and incident response procedures

This approach ensures end-to-end cybersecurity coverage and aligns with standards like ISO/SAE 21434, making compliance and security equally prioritized throughout development.

Role of AI in Automotive Cybersecurity

As connected vehicles become more complex, traditional rule-based security approaches often fall short in keeping up with sophisticated and evolving threats. Artificial Intelligence (AI) and machine learning (ML) are revolutionizing automotive cybersecurity by enabling intelligent, real-time, and predictive protection mechanisms for ECUs, in-vehicle networks, and cloud-connected systems.

How AI and Machine Learning Enhance Threat Detection

AI and ML enable vehicles to autonomously identify, assess, and respond to cyber threats by analyzing massive volumes of real-time data generated by ECUs and vehicle networks.

Key benefits include:

• Behavioral anomaly detection based on learned patterns of normal ECU communication
• Zero-day threat identification by detecting deviations that traditional methods may overlook
• Reduced false positives through continuous learning and model refinement
• Automated incident response, such as isolating compromised nodes or triggering fallback modes

By learning from historical and real-time data, AI enables faster and more accurate threat detection across the entire automotive cybersecurity lifecycle.

Adaptive Algorithms for Real-Time Monitoring of In-Vehicle Networks

AI-powered adaptive algorithms continuously monitor traffic across in-vehicle networks like CAN Bus, LIN, and Automotive Ethernet. These algorithms can:

• Baseline ECU communication behavior under normal operating conditions
• Detect abnormal message rates, unexpected commands, or spoofed messages
• Dynamically adjust detection thresholds to accommodate different driving modes (e.g., parking, highway)
• Operate within the constraints of embedded systems, using lightweight, edge-deployable AI models

This adaptive capability is crucial for maintaining real-time protection in the face of shifting network behavior and attack patterns.

Predictive Analytics in Automotive Cybersecurity for Connected Vehicles

Predictive analytics uses AI to forecast potential cybersecurity threats before they occur, enabling proactive risk management.

Applications include:

• Analyzing telematics and OTA update data to detect early signs of compromise
• Identifying vulnerable ECU or software components based on historical trends
• Assessing supplier risk by tracking software provenance and update frequency
• Supporting threat intelligence platforms by correlating data across vehicle fleets and external sources

This predictive power helps OEMs and Tier-1 suppliers strengthen their automotive cybersecurity posture while reducing exposure to emerging risks.

In summary, AI transforms automotive cybersecurity from a reactive task into a real-time, predictive, and adaptive defense system, safeguarding the future of connected and autonomous vehicles.

Leveraging AI with Visure Requirements ALM Platform for Automotive Cybersecurity for ECUs & In-Vehicle Networks

As vehicles become increasingly connected, ensuring automotive cybersecurity for Electronic Control Units (ECUs) and in-vehicle networks is mission-critical. The complexity of managing compliance, threat modeling, and secure-by-design practices across multiple vehicle systems and suppliers demands a modern, AI-driven solution. This is where the Visure Requirements ALM Platform excels.

AI-Driven Cybersecurity in the Automotive Development Lifecycle

The Visure Requirements ALM Platform integrates artificial intelligence to enhance every stage of the automotive cybersecurity lifecycle, aligning with standards like ISO/SAE 21434 and UNECE WP.29. It empowers engineering teams to:

• Automate cybersecurity requirement elicitation from regulatory documents
• Generate threat models and identify attack surfaces across ECUs and network interfaces
• Maintain full requirements traceability from cybersecurity risks to mitigation strategies
• Ensure end-to-end coverage across CAN Bus, LIN, FlexRay, and Automotive Ethernet

By using Visure, organizations gain the confidence that cybersecurity is built-in, not bolted on.

How AI Enhances Risk Assessment and Threat Modeling

Visure’s AI capabilities streamline risk assessment and threat modeling by:

• Automatically mapping assets, threats, and mitigations across vehicle systems
• Supporting TARA (Threat Analysis and Risk Assessment) aligned with ISO/SAE 21434
• Detecting incomplete or conflicting security requirements using natural language processing
• Recommending best practices for securing in-vehicle networks and ECUs

This reduces manual overhead while improving the accuracy and consistency of security requirements across the product line.

Seamless Integration with Compliance & Cybersecurity Standards

Visure ensures traceability and compliance by integrating directly with:

• ISO/SAE 21434 cybersecurity artifacts
• ISO 26262 functional safety processes
• ASPICE and UNECE WP.29 frameworks
• Existing test, simulation, and validation tools for ECU-level security verification

With Visure, you can automate audit reporting, simplify reviews, and guarantee that every cybersecurity requirement is tracked, validated, and verified, from design to deployment.

Accelerating Secure Vehicle Development with Real-time Traceability

Visure’s live traceability and impact analysis features allow teams to:

• Visualize how cybersecurity requirements connect to ECUs, software components, and test cases
• Quickly assess the impact of a regulatory change or new vulnerability
• Maintain synchronized updates across hardware, software, and documentation
• Streamline secure Over-the-Air (OTA) update strategies with traceable patch workflows

This delivers true end-to-end cybersecurity lifecycle management, essential for modern, connected automotive systems.

The Visure Advantage for Automotive Cybersecurity

By combining powerful AI capabilities with robust requirements management, traceability, and compliance tools, Visure enables automotive teams to:

• Reduce cybersecurity risks in ECUs and in-vehicle networks
• Accelerate compliance with evolving standards and regulations
• Streamline threat modeling, testing, and validation
• Maintain agile and secure development across distributed teams

Conclusion

The growing complexity of modern vehicles, driven by advanced Electronic Control Units (ECUs), in-vehicle networks, and connected vehicle technologies, makes automotive cybersecurity a top priority. As cyber threats evolve, so must the strategies and tools used to defend critical vehicle systems.

From understanding vulnerabilities in CAN Bus and infotainment systems to implementing AI-driven risk assessments, robust cybersecurity lifecycle management is essential to protect against potential breaches and ensure regulatory compliance with standards like ISO/SAE 21434.

Integrating artificial intelligence and comprehensive requirements traceability through platforms like the Visure Requirements ALM Platform empowers engineering teams to proactively identify risks, automate threat modeling, and maintain full end-to-end cybersecurity coverage across all ECUs and network layers.

Stay ahead of evolving threats with the industry’s most advanced Requirements Engineering Software for automotive cybersecurity.

Check out the 30-day free trial of the Visure Requirements ALM Platform and experience how AI can help you build secure, compliant, and resilient connected vehicles.