Jaguar & Land Rover Vehicles Impacted by Electrical Power Loss Bug

If you drive a recent Jaguar or Land Rover Mild Hybrid Electric Vehicle (MHEV), a major safety notice may impact your vehicle. On September 17, 2026, Jaguar Land Rover North America, LLC (JLR) issued a safety notification affecting 23,677 vehicles due to a critical defect in the DC-DC converter system that can cause a sudden loss of drive power and exterior lighting while driving.

This action (NHTSA Campaign Number: 26V-599) significantly expands a previous April 2026 safety campaign (26V-248 / JLR Campaign Code E008).

What is the Defect?

The issue impacts the DC-DC converter system in certain JLR Mild Hybrid vehicles. Two separate problems can cause the converter to fail:

• Electrical Overload: Insufficient load balancing during periods of high electrical demand can overload the DC-DC converter, causing it to malfunction.
• Software Error: A software bug introduced into the vehicle's code can cause the DC-DC converter to go completely offline at startup under specific conditions.

What Happens If the DC-DC Converter Fails?

When the DC-DC converter stops working, the vehicle loses its 12-Volt charging system. This leads to a cascade of failure symptoms while driving:

1. Warning Light: Within 10 seconds of failure, a red warning message reading “Stop Safely Electrical Fault Detected” appears on the dashboard display.
2. Progressive System Shutdown: As the 12V battery drains, driver assistance and safety systems begin disabling one by one (e.g., Lane Keep Assist Disabled, Suspension Fault, Stability Control Fault).
3. Transmission Shift & Engine Shutdown: Continued driving forces the vehicle into Neutral with a Gearbox Fault warning. Shortly after, the engine shuts down, and the vehicle coasts to a stop.
4. Loss of Lighting: Eventually, the battery loses enough power to sustain exterior lights, leaving the vehicle stalled without headlights or hazard lights, which significantly increases the risk of a crash.

Which Models Are Affected?

The national safety action covers phase 2 DC-DC converter models built up to and including the 2024 Model Year (24MY) across the following vehicle lines:

• Land Rover Range Rover (2020–2024)
• Land Rover Range Rover Sport (2019–2024)
• Land Rover Range Rover Velar (2021–2024)
• Land Rover Range Rover Evoque (2020–2024)
• Land Rover Defender
• Land Rover Discovery & Discovery Sport
• Jaguar F-Pace & E-Pace

How Did JLR Discover the Issue?

Following the initial April 2026 safety action for phase 1 converters (NHTSA 26V-248), JLR's Product Safety and Compliance Committee (PSCC) conducted hardware stress testing on newer converters. When hardware testing failed to reproduce the issue, engineers conducted a forensic, line-by-line software code review alongside an AI predictive model trained on vehicle data.

The investigation confirmed that phase 2 converters exhibit a similar elevated risk of failure. Between April 2024 and September 2026, JLR received 393 claims and field reports in the U.S. related to this issue. Fortunately, no accidents, injuries, or fires have been reported to date.

The Repair & Next Steps for Owners

• The Fix: Authorized dealers will update the vehicle's software. The update resolves the startup bug, restores proper load balancing, and introduces a protective “limp-home” mode with power de-rating if the converter ever goes offline.
• Notification Dates: Interim notification letters alerting owners to the safety risk are expected to be mailed by November 13, 2026. Follow-up letters will be sent once the final software update is ready at dealerships.

What Are Your Rights Under the Lemon Law?

If your Land Rover or Jaguar has repeatedly experienced electrical faults, lost power while driving, or required multiple service appointments at the dealership, you do not have to handle the burden alone. State Lemon Laws and federal warranty laws protect consumers who purchase or lease defective vehicles.

You may be entitled to a refund or replacement if:

• Your vehicle has been in the repair shop for an extended period for the same defect.
• The dealership has been unable to resolve recurring safety issues after multiple attempts.
• The defect substantially impairs the vehicle’s use, value, or safety.

Has your vehicle suffered from sudden power loss or electrical faults? Contact an experienced Lemon Law attorney today to learn about your legal options.