Table 1 shows one common engine and engine cooling related problems of the 2021 Land Rover Discovery.
| Problem Category | Number of Problems |
|---|---|
| Engine And Engine Cooling problems |
I am filing a safety complaint regarding a sudden and complete loss of power event while driving my 2021 Land Rover Discovery. The vehicle experienced a DC-DC converter failure with no warning, resulting in a sudden shutdown. The engine lost power, critical systems went offline, and I was unable to shift the vehicle into neutral. The vehicle became immobilized in active traffic, creating a dangerous situation. This incident occurred without warning and left me with no ability to safely move the vehicle out of traffic or rely on normal emergency functions. This presents a serious safety hazard to both the driver and others on the road. The vehicle has been at the dealership since mid-January 2026. The dealer has stated that the DC-DC failure caused additional component failures. However, no root cause has been identified beyond “internal failure,” and I have not been provided confirmation that the system has been properly tested or that the issue will not recur. I am concerned that this failure can cause cascading electrical issues, including loss of the 12v system, impacting multiple critical vehicle functions at once. The lack of a clear diagnosis and verified repair raises concerns about reliability and safety. Given the sudden loss of power, inability to move the vehicle, and absence of a confirmed root cause or validated repair, I am formally requesting that the national highway traffic safety administration open a defect investigation into the mhev/DC-DC system. This failure creates a significant safety risk, including vehicles becoming immobilized in active traffic without warning. The risk of recurrence without a defined cause is especially concerning and may indicate a broader issue.