Plug-in Hybrid Coolants: Colour Doesn't Prove a Match

Two cooling systems on a plug-in hybrid: don't judge coolant by colour

Scope: 2026 Qin L DM-i, China mainland; PDF pp. 373–374; filling to be confirmed by professionals

The same colour isn't the same specification

This car's information distinguishes between engine coolant and the coolant for the motor and electronic controls, and restricts mixing different brands and types. Colour is only appearance and cannot replace the official specification. When choosing, first state which system it is for, the exact vehicle version and the original-equipment requirement; don't order a "universal new-energy coolant" and then look for reasons why it fits. ^[1]

Orders should state how compatibility was checked

We suggest the quote states the product identity and the basis for it meeting this car's requirements. If old repair invoices show unclear materials, check with the workshop rather than filling the gaps from memory. One system not needing service for a long time does not mean the other is the same. Specific intervals and work are set by this car's own documents, not by another model's. ^[1]

Owners don't check a hot system

If you see an abnormal temperature, a persistent leak or a related warning, stop using the car under heavy load and get help. Don't open caps, mix coolants, add rust inhibitor or use water as a stop-gap yourself. This article gives no fill quantities, bleeding steps or procedures for any related part; a professional workshop should find the cause and keep an accurate record of the materials used. ^[1]

Sources

[Source 1] BYD China official website: 2026 Qin L DM-i Owner's Manual (in Chinese) (public PDF on the official website)
https://www.byd.com/material/domestic-official/user-manual/dynasty/2026%E6%AC%BE%E7%A7%A6L%20DM-i%E7%94%A8%E6%88%B7%E6%89%8B%E5%86%8C20260417.pdf
Verified: 2026-10-03; page publication date not confirmed.

This article contains information-organising suggestions from the editorial team; it is not a manufacturer repair procedure.