2004 Toyota Prius 1.5L Hybrid electric · ML54 RKU

The 2004 Toyota Prius presents a largely stable and improving mechanical picture. The most recent test on 12 November 2025 at 80,420 miles passed cleanly with zero defects, a notable shift from the advisory recorded just two years prior. This suggests a recent focus on addressing corrosion-related issues rather than ignoring them. The mileage pattern tells a story of very light, consistent use. Between November 2024 and November 2025, the car covered just 4,583 miles. The annual average sits at roughly 3,655 miles, well below the UK typical of 8,000 to 12,000. Such low mileage often means reduced wear on drivetrain components and brakes, but it also raises the risk of moisture ingress and corrosion from prolonged standing, which aligns with the historical advisory. That advisory, recorded on 13 November 2023 at 72,741 miles, flagged corroded rear brake pipes covered in grease or other material. Brake pipe corrosion is a serious structural concern, particularly on older vehicles where underseal degrades over time. The fact that this defect vanished from subsequent tests implies the pipes were either cleaned and treated or replaced entirely. A buyer should still inspect the underside thoroughly, paying close attention to the condition of the brake lines around the rear axle and fuel tank area for any signs of fresh surface rust or weeping fluid. Beyond the brake lines, the Prius hybrid system demands attention. The inverter coolant pump and the high-voltage battery cooling fan are common failure points on this generation. Listen for whining from the rear cabin area and check the battery fan intake for blockages. Suspension bushes and coil springs rarely appear on MOT advisories until severely degraded, so a physical inspection of the front lower arms and rear trailing arms is advisable. The clean recent MOT is encouraging, but the car's age and low mileage mean rubber perishing and corrosion remain the primary threats to long-term structural integrity.