For DM-i cooling and thermal-management condition, first define what a pass looks like. Then compare the actual vehicle with that standard using documents, inspection media and destination advice.
Decide DM-i cooling and thermal-management condition
Start by confirming the exact DM-i model and market because coolant circuits, controls and service information can differ. With the car genuinely cold, inspect coolant levels and specified fluids, reservoirs, hoses, radiators, condenser, fans, underbody protection and visible leaks. Then evaluate engine, hybrid and charging operation through a controlled warm-up, drive and hot restart. Keep this route connected to the broader used-DM-i inspection and battery-health pages.
Evidence for DM-i cooling and thermal-management condition
Collect service records, cold-start video, close photographs before cleaning and a complete scan. Record ambient conditions, coolant and battery temperatures where supported, fan behaviour, cabin conditioning, engine starts, EV-to-HEV transitions and any power limitation. Inspect for impact around front heat exchangers and the battery underside. If charging is available, note whether thermal warnings or interruptions occur during a controlled session. Use the complete used DM-i inspection for hybrid operation and the battery evidence route for high-voltage condition.
Export and ownership exposure
The combustion engine may remain off during a short demonstration, so an EV-only test cannot prove the complete system. Fresh coolant, a cleared warning or a clean undertray can hide repair. Wrong fluid, trapped air, blocked airflow or collision damage may affect several circuits. High-voltage diagnosis and coolant work require qualified procedures; do not open hot systems or infer battery health from temperature alone.
Apply the decision to a real candidate
For a DM-i intended for hot-climate motorway use, require a route that reaches stable operating temperature and includes repeated hybrid transitions. If the engine repeatedly stops with warnings, temperatures become unstable or one coolant circuit shows residue, keep the VIN on hold for pressure testing and qualified diagnosis. Price a confirmed repair, not an assumed thermostat or sensor.
Build the VIN-linked record
Keep one dated decision log. Each entry should identify the source, vehicle, finding and next action for exact dm-i identity, cold coolant inspection, heat-exchanger condition. Attach commercial evidence separately so technical acceptance is not rewritten by negotiation.
Common approval mistakes
The common shortcut is treating a model-level fact as candidate proof. Verify exact dm-i identity physically and on records, qualify temperature and fan data by destination, and exclude any unconfirmed feature from the value calculation.
Close the decision
Before this file advances, reconcile exact dm-i identity with the vehicle and its documents, and price any unresolved heat-exchanger condition consequence. Record who controls hot restart and final scan after arrival. If the answer exists only in an informal message, move it into the dated approval record or leave the candidate on hold.
Independent review for DM-i cooling and thermal-management condition
For DM-i cooling and thermal-management condition, assign each approval field to a reviewer with the relevant competence. Record candidate evidence for exact dm-i identity, cold coolant inspection, heat-exchanger condition, then obtain destination or commercial confirmation for temperature and fan data, hybrid transition test, hot restart and final scan where required. Every conclusion should identify its source, date and VIN. If two reviewers interpret a field differently, keep it open until the underlying document, photograph, diagnostic result or written third-party answer resolves the difference.
Arrival controls for DM-i cooling and thermal-management condition
Before loading, freeze the accepted VIN, identity, condition, odometer, warning state, keys, accessories and unresolved exceptions. On arrival, compare those records before cleaning, repair, software changes or routine use. Recheck any open item involving temperature and fan data, hybrid transition test, hot restart and final scan, preserve evidence for a timely carrier or supplier claim, and update the ownership file with actual destination findings and costs.
Define a pass before viewing candidates
The pass standard for DM-i cooling and thermal-management condition should combine legal suitability, usable energy support and total ownership cost. Write the non-negotiable evidence for exact dm-i identity and cold coolant inspection, then state the maximum acceptable uncertainty around heat-exchanger condition. A candidate that fails a non-negotiable item should not be rescued by cosmetic equipment or a small discount. This protects the shortlist from changing criteria whenever an attractive listing appears.
Make exceptions explicit
Some limits may be acceptable when they are understood and priced. Record each exception, its consequence, the party responsible after delivery and whether it affects registration, charging, safety, resale or normal operation. Pay particular attention to temperature and fan data, hybrid transition test and hot restart and final scan. The buyer should sign off the exception in the same file as the VIN evidence so it cannot later be mistaken for an undisclosed defect.
Inspect Song Plus DM-i Cooling and Thermal Management: approval checklist
Mark each item confirmed, unresolved or rejected and retain its evidence under the candidate VIN.
- Exact DM-i identity
- Cold coolant inspection
- Heat-exchanger condition
- Temperature and fan data
- Hybrid transition test
- Hot restart and final scan
Primary references
These manufacturer pages establish context; actual specifications remain market-, year- and VIN-dependent.
Official BYD owner-manual library ↗Buyer questions about DM-i cooling and thermal-management condition
Can an EV-mode drive prove a DM-i cooling system is healthy?
No. The test must exercise the relevant engine, hybrid and charging circuits.
Does one normal temperature reading prove battery health?
No. Review diagnostics, charging behaviour and physical condition together.
Can ordinary coolant be added?
Use only the specification and procedure for the exact vehicle.