I. Case Background: Sewage Treatment Vehicle Procurement by a Municipal Sanitation Department in Taiyuan City In winter 2025, a municipal sanitation department in Taiyuan City procured two sewage treatment vehicles—model EHY5045TWCE6, manufactured by Hubei Chengli Special Purpose Vehicle Co., Ltd.—via public tender to meet upgraded urban sewage treatment infrastructure requirements. These vehicles are primarily deployed for emergency maintenance of urban sewage pipelines and operation & maintenance of small-scale sewage treatment stations, with a budget capped at approximately RMB 339,000 (per publicly available tender information). After delivery, the customer reported outstanding cold-weather engine start-up performance and hydraulic system stability—key highlights of this procurement. As one of China’s largest special-purpose vehicle manufacturers, Chengli Special Purpose Vehicle has served over 500 municipal sanitation units nationwide. The EHY5045TWCE6 model delivered in this case is built on the Dongfeng 3308 chassis, equipped with a China VI-compliant engine, and fully certified for nationwide registration and annual inspection. The customer’s acceptance team conducted rigorous, item-by-item inspections per industry standards to ensure the vehicles meet operational requirements under Taiyuan’s harsh winter climate. II. Ten Critical Inspection Items Upon Vehicle Acceptance Based on the actual acceptance process from the Taiyuan procurement case, the following ten items must be verified during vehicle acceptance—with particular emphasis on cold-weather engine start-up performance and low-temperature hydraulic stability for northern winter operations: 1. Chassis and Engine Start-Up Test: Under ambient temperatures ranging from −10°C to −20°C, verify whether the engine starts smoothly within three attempts, without abnormal vibration or noise. The Dongfeng chassis equipped on the EHY5045TWCE6 features a cold-start assist system, which passed the customer’s real-world test. 2. Hydraulic System Low-Temperature Stability: After startup, confirm whether hydraulic oil temperature reaches operating temperature (≥30°C) within five minutes, and check for leaks or abnormal noise from the hydraulic pump and lines. In this case, the hydraulic system maintained stable pressure throughout four consecutive hours of winter operation in Taiyuan. 3. Sewage Treatment Function Verification: Introduce simulated sewage (containing slurry and debris) to test the full workflow—suction, filtration, and discharge—for efficiency; required throughput must reach ≥90% of the rated capacity. The EHY5045TWCE6’s rated treatment capacity is 10 m³/h; actual measured throughput was 9.5 m³/h. 4. Tank Sealing and Corrosion Resistance Inspection: Verify that the internal tank coating is intact—free of bubbles or peeling—and conduct a 30-minute water-fill static test to inspect weld seam integrity. The customer used an ultrasonic thickness gauge to confirm tank wall thickness compliance with official certification parameters. 5. Electrical System and Instrument Panel: Ensure all indicator lights, warning lights, and control panel buttons function properly; instrument readings (e.g., oil pressure, coolant temperature, engine speed) must match actual vehicle conditions. 6. Tires and Braking System: Confirm tire model and tread wear comply with certification requirements; verify no leakage in brake lines and braking response time ≤0.5 seconds. 7. Vehicle Markings and Lighting: Check secure installation of reflective markings and warning lights per national standards; ensure proper operation of headlights, turn signals, and fog lamps. 8. Onboard Documentation and Tools: Verify completeness of documents including the ‘Motor Vehicle Whole-Vehicle Factory Certificate of Conformity’, ‘Chassis Certificate of Conformity’, and ‘User Manual’; confirm availability of all standard tools (e.g., jack, fire extinguisher). 9. Winter Maintenance Kit Inspection: Confirm installatio