Over-the-Air (OTA) Updates in EVs and How it works?

Over-the-Air (OTA) Updates in EVs are wireless software or firmware updates sent remotely by an automaker to a connected vehicle. They can fix software bugs, update infotainment, strengthen cybersecurity, and, on suitably designed vehicles, recalibrate systems such as battery management, charging, powertrain, or driver assistance without requiring a conventional workshop software flash.

That makes OTA much more important in 2026 than a simple convenience feature. As vehicles become software-defined vehicles (SDVs), software increasingly determines how an EV charges, manages its battery, delivers power, communicates with the driver, and protects itself from cybersecurity threats.

OTA therefore changes a basic idea of vehicle ownership: the car that leaves the showroom does not necessarily remain technologically identical throughout its life.

Over-the-Air (OTA) Updates in EVs: Key Takeaways

• OTA means remotely updating vehicle software through a wireless connection, normally cellular or Wi-Fi.
• SOTA generally deals with software applications and user-facing functions, while FOTA can update firmware controlling deeper electronic systems.
• OTA can affect infotainment, navigation, cybersecurity, charging behavior, BMS calibration, ADAS, and other systems, depending on the vehicle architecture.
• Downloads and installations are different stages: a vehicle may download an update while being used but require parking before installation.
• Modern OTA systems use authentication, digital signatures, encryption, and controlled installation procedures to reduce cybersecurity and update-failure risks.
• Not every EV supports the same OTA depth. Some vehicles can update only infotainment, while newer software-defined platforms may update many electronic control units.
• In India, AIS-189 addresses Cyber Security Management Systems, and AIS-190 addresses Software Updates and Management Systems, reflecting the growing regulatory importance of connected-vehicle software.

What Are Over-the-Air (OTA) Updates in EVs?

An OTA update is the remote delivery of software, configuration data, or firmware to a vehicle using wireless communication.

Think of the process as conceptually similar to updating a smartphone, but technically far more demanding. A phone update can inconvenience the user if it fails. A vehicle update could potentially affect braking, propulsion, charging, or safety systems, so automotive updates require much stricter validation and control.

ISO 24089:2023 specifically addresses software update engineering for road vehicles, covering organizations, vehicles, vehicle systems, electronic control units, infrastructure, and the preparation and deployment of update packages.

This is one reason the phrase “software on wheels” is increasingly appropriate.

Software-defined vehicles can enable, improve, or alter functions through software rather than requiring every change to be implemented through new physical hardware. Research into SDVs also highlights OTA as an important mechanism for maintaining vehicle software security and stability over time.

What Is the Difference Between SOTA and FOTA?

OTA is often divided into SOTA and FOTA, although the exact terminology and boundaries can vary between manufacturers.

Polestar similarly describes SOTA as covering software such as navigation and infotainment, while FOTA reaches deeper into firmware associated with hardware such as the powertrain or battery-management system.

The key distinction for buyers is not the terminology itself. It is how much of the vehicle can actually be updated remotely.

An EV advertised as having OTA updates may support nothing beyond maps and infotainment. Another vehicle may be architected to update dozens of ECUs and modify meaningful vehicle behavior.

How Do Over-the-Air Updates Work in an EV?

The simplest answer is

Automaker develops update → tests and signs it → cloud distributes it → vehicle downloads it → verifies authenticity → installs it under controlled conditions → validates the new version.

Here is the process in more detail.

1. Engineers Develop and Validate the Update

The automaker or an authorized supplier develops a new software build.

It may contain:

• bug fixes,
• cybersecurity patches,
• improved navigation,
• charging refinements,
• BMS calibration,
• ADAS changes,
• user-interface improvements,
• compatibility updates,
• new vehicle functions.

Safety-related software normally goes through substantially more validation than an entertainment-app update.

2. The Update Is Packaged and Digitally Authorized

The manufacturer packages the software for the correct vehicle configuration.

This stage is critical because different production batches can contain different ECUs, hardware revisions, or supplier components.

Modern automotive software-management processes therefore need accurate information about which software versions belong on which vehicle configurations. ISO 24089 specifically highlights the importance of individual vehicle configuration information as software-update campaigns become more frequent.

A cryptographic signature can then allow the vehicle to check whether the package came from an authorized source and whether it was altered after signing.

3. The Automaker Launches an OTA Campaign

The update is typically placed on the manufacturer’s cloud infrastructure.

The OEM may not send it to every vehicle simultaneously. A staged rollout can target:

• a limited test fleet,
• a particular VIN group,
• certain regions,
• specific hardware versions,
• selected model years,

before wider deployment.

This gives the manufacturer an opportunity to identify unexpected real-world issues before the update reaches the entire fleet.

4. The Vehicle Downloads the Package

The update normally reaches the vehicle through:

• 4G/5G cellular connectivity
• Wi-Fi

A vehicle’s Telematics Control Unit (TCU) often provides the bridge between the cloud and the in-vehicle electronic network.

Rambus describes a typical automotive OTA flow in which a manufacturer’s device-management system places the software in the cloud; the connected vehicle downloads and verifies it before installation.

A crucial distinction is that downloading does not necessarily mean installing.

Some cars can download a package in the background while being driven but will not flash safety-relevant software until the vehicle is parked.

5. The Vehicle Authenticates the Update

Before installation, the vehicle should verify:

• digital signature,
• package integrity,
• software compatibility,
• target ECU,
• software version,
• permitted update sequence.

This security layer helps prevent a modified or malicious software package from being accepted as legitimate.

Automotive OTA is therefore not simply “send a file to the car.”

It is part of a much larger cybersecurity architecture.

6. The Vehicle Checks Installation Conditions

Depending on the vehicle and update, installation may require:

• vehicle parked,
• transmission in Park,
• sufficient high-voltage battery charge,
• adequate 12V battery condition,
• doors or systems in a prescribed state,
• charging disconnected or connected, depending on OEM instructions,
• sufficient installation time.

For example, Polestar states for the process described on its OTA explainer that installation requires at least 40% battery charge and roughly 90 minutes of downtime. Those are Polestar-specific conditions—not universal requirements for every EV.

This distinction is important. Owners should follow the instructions displayed by their own vehicle, rather than applying another manufacturer’s battery threshold.

7. Software Is Installed on the Target ECU

After the car enters the required safe state, the new software is written to the relevant system.

That ECU could control anything from the infotainment display to a battery-management function.

Some architectures use redundancy or A/B software partitions, allowing a known-good software image to remain available if installation of the new version cannot be completed successfully.

Other systems use different recovery strategies.

The objective is the same: avoid leaving the car unusable because an update was interrupted or corrupted.

8. The Vehicle Verifies and Reports the Result

After installation, the vehicle can restart affected modules, verify the new software and report its update status to the manufacturer’s backend.

The driver may then see a release note explaining:

• new features,
• fixed problems,
• changed behavior,
• security improvements,
• known limitations.

Why Is OTA More Important for EVs?

OTA exists in combustion-engine vehicles too. But it has particular importance in EVs because so much of an electric vehicle’s behaviour is controlled digitally.

The software can influence:

• battery charging,
• battery cooling and heating,
• motor response,
• regenerative braking,
• range prediction,
• DC fast-charging preparation,
• energy consumption,
• thermal management.

Tata Motors has highlighted OTA’s potential to fine-tune BMS operation, charging efficiency, and regenerative braking as vehicles become increasingly software-driven.

This does not mean every OTA update increases range or charging speed. Hardware limits still exist.

Instead, software can optimize how existing hardware is managed within the manufacturer’s safety and durability boundaries.

What Role Does OTA Play in EV Battery Management?

The Battery Management System (BMS) is one of the most important computers in an EV.

It helps monitor and manage:

• State of Charge (SoC),
• State of Health (SoH),
• temperature,
• voltage limits,
• cell balance,
• charging and discharging limits,
• battery protection strategies.

An OTA-capable architecture can allow an automaker to refine BMS software based on testing, field data or discovered problems.

Potential changes can include:

Charging-curve optimization

Software determines how much charging power the pack accepts at different temperatures and states of charge.

A revised calibration may improve charging behaviour where the battery and charging hardware safely allow it.

Thermal-management refinements

The BMS can change how aggressively the vehicle heats or cools its battery.

That can matter for fast charging, efficiency, and battery protection.

Cell-balancing strategies

Updates may refine how the BMS keeps cell groups operating within appropriate voltage ranges.

Battery diagnostics

Connected vehicles can provide diagnostic information that helps manufacturers identify trends or software problems.

Everything PE notes that OTA can support BMS firmware changes, charging-parameter optimization, thermal-management settings and monitoring related to SoC, SoH, and cell balancing.

Can an OTA Update Increase an EV’s Range?

Yes, theoretically and sometimes in practice—but an OTA update cannot magically create additional physical battery capacity.

Range may improve if software:

• reduces energy consumption,
• optimizes motor control,
• improves thermal management,
• refines battery preconditioning,
• changes usable battery buffers where technically justified,
• improves energy recuperation,
• improves range estimation.

But owners should distinguish between actual efficiency improvement and simply a change in the range displayed by the dashboard.

An update can recalibrate the vehicle’s range estimator without changing the amount of energy stored in the battery.

What Can OTA Updates Change?

Modern automotive OTA capability can cover a surprisingly large range of systems.

A real-world example comes from Polestar. Its OTA program has delivered updates covering infotainment, climate controls, charging and driving-related functionality, while a 2025 release for Polestar 3 added features and software-stability improvements.

Again, capability varies dramatically by model.

What Are the Benefits of Over-the-Air Updates in EVs?

1. Fewer Workshop Visits

Many software fixes can be delivered remotely instead of requiring a diagnostic-tool connection at a dealership.

That reduces inconvenience for the owner and can reduce service workload for the manufacturer.

2. Faster Bug Fixes

A software issue discovered across thousands of vehicles can potentially be corrected through a centrally managed update campaign.

3. Better Cybersecurity

Connected cars need continuous security maintenance.

OTA allows manufacturers to distribute security patches rather than waiting for every affected vehicle to visit a workshop.

4. Continuous Feature Improvement

New functionality can sometimes be added months or years after the vehicle was sold.

5. Better Fleet Management

OEMs can manage software versions across large fleets and identify which vehicles have or have not successfully installed an update.

6. Lower Recall-Service Burden

Some software-related remedial actions may be delivered remotely.

However, OTA does not eliminate vehicle recalls. Regulators may still classify a safety problem as a recall even when the manufacturer can provide the remedy through software.

OTA Updates vs Traditional Dealership Updates

OTA is therefore not a replacement for service centres.

Software cannot replace a damaged battery module, worn suspension component or failed cooling pump.

What Are the Challenges and Risks of OTA Updates?

OTA creates convenience, but it also creates a much larger cybersecurity and systems-engineering problem.

a) Cybersecurity

An attacker must not be able to impersonate the manufacturer or inject unauthorized software.

Threat categories can include:

• spoofing,
• tampering,
• unauthorized privilege escalation,
• information leakage,
• denial-of-service attacks.

Rambus highlights similar threat classes when discussing automotive OTA security.

The supplied IEEE research also emphasizes that OTA distribution creates security and network-performance concerns, particularly where connected vehicles and edge infrastructure participate in dissemination. OTA_Software_Defined_Vehicles

Its proposed fog-based architecture investigated malicious-node detection and more efficient update distribution. That research is useful for understanding future architectures, although it should not be mistaken for the standard production architecture used by every modern EV.

b) Poor Connectivity

Large software packages can take substantial time to download over weak mobile networks.

For Indian owners, this can be particularly relevant where vehicles are parked in basements or used in areas with inconsistent connectivity.

Fortunately, well-designed systems can pause and resume downloads rather than restarting them.

c) Failed Installation

Loss of power or software corruption during a firmware flash is more serious than losing internet connectivity during the download stage.

This is why robust OTA designs incorporate validation, recovery procedures and appropriate installation conditions.

d) Legacy Vehicle Architecture

Older vehicles frequently contain numerous ECUs developed independently by different suppliers.

Even when the vehicle has a connected infotainment system, those deeper controllers may never have been designed for remote flashing.

Sonatus notes that many existing vehicles have historically been limited mainly to infotainment, navigation and selected ADAS updates because legacy electrical/electronic architectures were not designed for comprehensive OTA operation.

OTA Cybersecurity and Regulation in 2026

OTA has become important enough that it is now part of formal automotive software governance.

UNECE R156

UN Regulation No. 156 concerns software updates and the Software Update Management System (SUMS) used by vehicle manufacturers.

The wider regulatory principle is significant: automakers need systematic processes for managing, documenting and safely deploying vehicle software updates.

ISO 24089

ISO 24089:2023 provides requirements and recommendations covering road-vehicle software update engineering across the vehicle lifecycle.

India: AIS-189 and AIS-190

For India, two standards are particularly relevant:

• AIS-189 – Cyber Security and Management System (CSMS)
• AIS-190 – Software Updates and Management System (SUMS)

ARAI documentation identifies both standards, while its AIS-190 interpretation manual specifically addresses requirements for manufacturers’ Software Update Management Systems.

This is an important 2026 development for Indian consumers. OTA is moving beyond being marketed merely as a connected-car feature; cybersecurity governance and controlled software management are increasingly fundamental to vehicle engineering.

Practical OTA Tips for EV Owners in India

Before starting a large software update:

• Check the manufacturer’s release notes.
• Ensure the battery meets the required minimum SoC.
• Do not assume another EV brand’s charging requirement applies to your vehicle.
• Park somewhere the car can remain undisturbed for the stated installation period.
• Use reliable Wi-Fi when recommended.
• Avoid initiating an update immediately before an important journey.
• Keep the car’s 12V electrical system healthy.
• Do not interrupt installation unless the manufacturer specifically instructs you to do so.
• If an update repeatedly fails, contact authorized support rather than attempting unofficial firmware modifications.

When buying an EV, also ask the salesperson a more useful question than “Does this car have OTA?”

Ask:

“Which vehicle systems can actually be updated over the air?”

That answer tells you far more.

Expert Insight from Electric Vehicle Talks

The next competitive battle in electric vehicles will not be fought only through bigger batteries, faster motors, and larger touchscreens. It will increasingly be fought through software lifecycle quality.

A manufacturer that builds excellent hardware but cannot reliably diagnose, update, and secure that hardware remotely may struggle to keep pace with software-first competitors.

For Indian buyers, OTA capability should therefore become part of the purchasing checklist. Buyers should investigate whether an EV supports only infotainment OTA or deeper vehicle-level FOTA, how long software support is promised, whether updates are free, and how the manufacturer handles failed installations.

There is also a second issue: OTA should not become an excuse to launch unfinished vehicles.

Continuous improvement is valuable, but buyers should expect core features and safety systems to work correctly at delivery. Software-defined mobility works best when OTA enhances a mature product—not when customers are effectively turned into permanent beta testers.

Looking further ahead, research is already exploring edge/fog architectures, vehicle-to-vehicle software distribution and more scalable ways of sending increasingly large updates to connected fleets. The supplied IEEE study, for example, explored fog nodes, software-defined networking and selected “pivot” vehicles to reduce network congestion and improve update dissemination.

That is a glimpse of where automotive software infrastructure could evolve as millions more connected vehicles join the road.

People Also Ask

1. What is OTA in automotive?

OTA in automotive means remotely delivering software, firmware or configuration updates to a connected vehicle through wireless networks instead of requiring the vehicle to be physically connected to workshop programming equipment.

2. How do Over-the-Air OTA updates work in EVs?

The manufacturer creates and validates an update, digitally authorizes it and distributes it through cloud infrastructure. The EV downloads the package via Wi-Fi or cellular connectivity, verifies it and installs it on compatible systems under controlled conditions.

3. Can OTA updates improve EV battery performance?

They can improve how the battery is managed by refining BMS, charging or thermal-control software. However, software cannot overcome the battery’s fundamental physical limitations.

4. Do OTA updates increase EV range?

Sometimes software optimization can improve efficiency or usable energy management. But not every reported range increase represents added physical battery capacity, and many updates simply improve range prediction.

5. Can you drive while an OTA update is installing?

For many major firmware updates, no. The download may happen in the background, but installation commonly requires the vehicle to be parked. Always follow the manufacturer’s instructions.

6. Are OTA updates safe?

Properly designed OTA systems use cryptographic authentication, integrity checks, controlled deployment and recovery mechanisms. Nevertheless, OTA increases cybersecurity responsibility because unauthorized software must be prevented from reaching critical vehicle systems.

7. Are OTA updates available in Indian EVs?

Yes, a growing number of connected vehicles sold in India provide OTA functionality, but the depth varies widely. Buyers should check whether OTA covers only infotainment or also vehicle controllers and firmware.

Over-the-Air (OTA) Updates in EVs FAQ

What happens if an OTA update fails?

The response depends on the vehicle architecture. A robust system may retry the installation, retain a previous working software image or invoke a recovery mode. If automatic recovery fails, service-centre intervention may be necessary.

Does an EV need to remain plugged in during an OTA update?

Not universally. Requirements vary by vehicle and software package. Some manufacturers specify only a minimum battery charge; others may give different instructions. Follow the update message displayed by your own EV.

What is the difference between an OTA download and installation?

The download transfers the software package to the vehicle. Installation actually replaces or changes software on a system or ECU. A car may therefore download an update while driving but require parking before installing it.

Can OTA fix a hardware problem?

No. OTA can sometimes change how hardware is controlled or diagnose a problem, but it cannot physically repair a faulty sensor, worn component, damaged battery module or broken charging port.

Are all OTA updates free?

Not necessarily. Bug fixes and security updates may be provided without additional charge, while manufacturers can also use OTA to deliver paid software features or optional performance upgrades. Buyers should check the manufacturer’s commercial policy.

Will OTA updates affect EV resale value?

Long-term software support can make a used EV more attractive because security fixes, compatibility updates, and feature improvements remain available. Conversely, discontinued software support could become an increasingly important consideration in used-EV valuation.

Conclusion

Over-the-Air (OTA) Updates in EVs have evolved from simple infotainment updates into a fundamental technology for connected and software-defined vehicles.

They can reduce workshop visits, accelerate software fixes, strengthen cybersecurity, and allow manufacturers to improve selected vehicle functions long after delivery. In advanced EV architectures, OTA may reach the battery-management system, charging logic, ADAS and powertrain-related controllers.

But deeper software control also demands deeper responsibility. Secure authentication, rigorous testing, rollback strategies, reliable connectivity, and long-term software support now matter almost as much as the update itself.

For buyers in India, the important question is no longer simply whether an EV “supports OTA.” The real questions are what can be updated, how securely it is updated, how long support will continue, and what happens when an update fails.

As EVs become increasingly software-defined, these factors will influence reliability, safety, ownership experience, and potentially resale value throughout the vehicle’s life.

For more EV technology explainers, buying guides, charging resources, ownership insights, and industry updates, explore Electric Vehicle Talks.

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