New Energy Vehicle Maintenance Guide

I. Definition

New energy vehicle (NEV) maintenance involves scheduled inspections, servicing, and component replacements for battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs). The primary objective is to maintain the optimal condition of the vehicle's "Three-Electric" system (battery, electric motor, and electronic control unit), alongside standard mechanical components, ensuring road safety and extending the vehicle's operating lifespan.

II. Key Differences from Conventional ICE Vehicle Servicing

The fundamental difference in servicing between NEVs and internal combustion engine (ICE) vehicles lies in their powertrains.

• Shift in Maintenance Focus: Conventional vehicle servicing centres on the engine system, requiring routine changes of engine oil, oil filters, and spark plugs. NEVs eliminate these complex mechanical systems, shifting the service focus entirely to the diagnostics and maintenance of the battery pack, drive motor, and electronic control unit.

• Fewer Service Wear Items: BEVs do not require engine oil, oil filters, or drive belts, significantly reducing the number of service items compared to petrol or diesel cars. This lowers routine maintenance complexity and ownership costs.

• Longer Service Intervals: Without mechanical engine wear and oil degradation, BEVs typically feature extended service intervals, commonly set at 10,000 km or 12 months.

III. Service Intervals and Key Checklist Items

NEV maintenance schedules follow a "mileage or time" rule, whichever comes first.

• First Service : Typically scheduled at 5,000 km or 6 months after delivery, whichever comes first. The initial service prioritises a thorough diagnostic check of the Three-Electric system and undercarriage to ensure all factory components operate within standard tolerances.

• Periodic Maintenance: Following the first inspection, pure electric vehicles (BEVs) typically require routine servicing every 10,000 km or 1 year. For hybrid models (PHEVs/HEVs), the schedule aligns more closely with ICE cars, typically every 7,500 km or 1 year.

Routine maintenance is broadly divided into two main categories: Three-Electric diagnostics and standard mechanical servicing:

(A) Three-Electric System Inspection (Core Focus)

• High-Voltage Battery System: The most critical component of an NEV. Technicians utilise dedicated diagnostic tools to assess the battery pack's State of Health (SOH), charge/discharge efficiency, thermal management system, and individual cell voltage balance.

• Electric Drive Motor: Technicians inspect the motor housing for physical damage, check wiring harness connections, and test for abnormal noise or vibration during operation. The motor cooling circuit is also inspected for proper circulation.

• Electronic Control System: Diagnostic scans are run on the Vehicle Control Unit (VCU) and Battery Management System (BMS), including necessary software/firmware updates to optimise efficiency and resolve system bugs.

(B) Standard Mechanical Items (Similar to ICE Vehicles)

• Braking System: Brake pad wear is measured (replacement is recommended when pad thickness reaches roughly one-third remaining), alongside checks on brake fluid level and moisture content.

• Cooling System: Inspection of coolant levels and hose seals for the drive motor, power electronics, and high-voltage battery. Crucial note: NEVs require specialised ultra-low conductivity coolant, which is not compatible with standard ICE radiator coolant; never top up or mix with unauthorised fluids.

• Tyres and Undercarriage: Tyre pressures, tread wear patterns, and rubber aging are checked, alongside suspension linkages, drive shafts, and chassis bushings for play or damage.

• Other Wear & Tear Items: Periodic replacement of the cabin air filter and windscreen wipers; scheduled replacement of reduction gear fluid (transmission fluid) and brake fluid; and inspection of the charging port pins for dirt, wear, or oxidation.

IV. Daily Usage and Preventive Care Tips

• Adopt Healthy Charging Habits: It is best practice to plug in once the state of charge drops to 20%–30% , avoiding regular 100% full charges unless required for long journeys. For day-to-day use, AC slow charging preserves battery health and reduces long-term degradation.

• Vehicle Storage and Washing Precautions: If parking the vehicle unused for an extended period (over a week), maintain the battery level between 50% and 70% . When washing, avoid direct high-pressure water jets inside the front bonnet bay and charging port to prevent water ingress into high-voltage components.

• Stick to Authorised Service Centres: High-voltage EV systems require dedicated tools, safety protocols, and certified technicians. Always send your car to an authorised 3S/4S dealership or certified EV service centre to safeguard your manufacturer warranty and high-voltage battery coverage.

V. Conclusion

NEV maintenance is straightforward, focusing largely on the proper health monitoring of the Three-Electric system. Compared to ICE vehicles, it offers fewer replacement parts and longer service intervals, while requiring higher technical precision during diagnostics. Adhering to the manufacturer's maintenance schedule, practising sensible charging habits, and using qualified technicians ensure your vehicle stays safe, reliable, and efficient over the long haul.