2025 BYD Seal U Boost DM-I Phev Auto Hybrid electric (clean) · WD75 XOO

As of September 2026, no DVSA MOT test history is available for this 2025 BYD SEAL U BOOST DM-I PHEV. Under current UK roadworthiness legislation, vehicles first registered less than three years before today's date are not yet required to undergo an annual MOT test, which fully accounts for the absence of recorded examination data. Without a verifiable pass or failure record, it is not possible to objectively evaluate the maintenance trend or confirm whether any advisories have previously been raised against the vehicle. Any prospective purchaser must therefore rely solely on physical inspection and supporting documentation rather than historical MOT evidence to establish the car's mechanical condition. The recorded mileage is unknown at the time of assessment, and there is insufficient MOT data to calculate an annualised usage rate against the vehicle's age. As a new-generation BYD plug-in hybrid, the SEAL U incorporates a petrol engine alongside high-voltage battery technology, meaning that both calendar-based component degradation and traditional mechanical wear pathways apply. Low or erratic mileage in such a vehicle can be particularly damaging, as short journeys without regular charging cycles prevent the high-voltage battery from reaching optimal operating temperature, potentially leading to reduced cell efficiency. Conversely, high mileage accumulated predominantly on the petrol powertrain may accelerate wear on the engine oil, brake discs, and tyres due to the additional mass of the hybrid system. Given the absence of MOT records, a prospective buyer should undertake a thorough independent mechanical inspection before purchase. The 12-volt auxiliary battery should be checked for adequate state of charge and load capacity, particularly if the vehicle has been left standing for extended periods, as lithium-ion traction batteries can deplete auxiliary supplies over time. The high-voltage system should also be verified for warning indicators on the dashboard, and all charging cables and connectors inspected for signs of damage or overheating. Brake discs and calipers should be examined for corrosion or seizing, especially given that regenerative braking reduces conventional caliper activity, leading to potential binding if the vehicle has been stationary for prolonged intervals. Further inspection should address tyre condition, including sidewall cracking or perishing common to lightly used vehicles, and verification of correct pressures in line with manufacturer specifications. All fluid levels should be examined, paying particular attention to engine oil condition, coolant concentration, and brake fluid hygroscopic content, as age-related fluid degradation remains a concern irrespective of mileage. Finally, the service book and digital service records should be reviewed to confirm that any initial manufacturer maintenance schedules have been observed, while a pre-purchase diagnostic scan is strongly recommended to identify any stored fault codes within the hybrid control modules that would not be evident during a standard road test.