Parts for your 2020 Mitsubishi Eclipse cross-Radiator cap

2020 Mitsubishi Eclipse Cross radiator cap: what’s actually fitted

For the 2020 Mitsubishi Eclipse Cross, a traditional radiator cap on the radiator itself isn’t used. Technical sources including the Mitsubishi Eclipse Cross Owner’s Manual (MY2020, Cooling System) and the Mitsubishi Motors Service/Workshop Manual (Cooling, Group 14) show a sealed radiator with the pressure cap located on the pressurised coolant reservoir (also called a degas/expansion tank). The factory parts catalogue likewise lists the pressure cap with the reservoir assembly, not the radiator. So, when people say “radiator cap” on this model, they’re really talking about the reservoir’s pressure cap.

Why go cap-less at the radiator? This cooling layout keeps the highest fill point at the reservoir, which helps purge air and stabilise pressure. It also reduces leak points, simplifies packaging under the bonnet, and suits the thermal demands of the turbocharged 1.5L engine used in this model year. The radiator stays sealed, and all filling, venting and pressure control happen at the reservoir.

• Better air separation and self-bleeding via the high-mounted reservoir
• Fewer joints and gaskets around the radiator, cutting leak risks
• More consistent operating pressure for improved cooling efficiency
• Easier top-ups and checks from a single, safe access point

Servicing on this vehicle focuses on the reservoir cap and coolant quality. The cap still does the classic job of holding pressure so the coolant’s boiling point stays higher, then venting and recovering coolant as it heats and cools. Under the bonnet, technicians will check the cap’s rubber seals and spring action, the reservoir’s coolant level and condition, and the system for any staining or weeping.

Only remove the reservoir cap when the engine is stone cold, and turn it slowly to release any residual pressure. If a cap pressure test shows it won’t hold the specified rating (use the rating printed on the cap or the service data for the exact figure), it’s time to replace it with a quality, correct-spec cap. Stick with the factory-approved coolant type and concentration, and keep the level between the ‘LOW’ and ‘FULL’ marks when cold.

• Signs the reservoir cap may be tired: recurring coolant loss or dampness around the cap, hoses that collapse as the engine cools, gurgling after shut-down, or overheating at low speeds.
• Where to add coolant: the pressurised reservoir only—never try to open the sealed radiator.

Technical references used: Mitsubishi Eclipse Cross Owner’s Manual (MY2020) Cooling System guidance, Mitsubishi Motors Service/Workshop Manual, Group 14 Cooling diagrams for the 1.5L turbo, Mitsubishi genuine parts catalogue indicating the pressure cap is paired with the reservoir, not the radiator.

• Does the 2020 Mitsubishi Eclipse Cross have a radiator cap?
  It doesn’t have a cap on the radiator. The pressure cap lives on the pressurised coolant reservoir, which controls system pressure and recovery. Service information and the owner’s manual for MY2020 point to the reservoir as the sole filling and pressure point.
• Where should coolant be topped up on this model?
  Top up only at the pressurised reservoir when the engine is cold. Bring the level to the ‘FULL’ line with the correct, factory-approved coolant mix. The radiator itself is sealed and has no filler neck.
• What cap rating should be used if the reservoir cap needs replacement?
  Use a cap with the pressure rating printed on the original cap or as specified in the workshop data for the vehicle’s VIN. Avoid generic “radiator caps” that don’t match the Eclipse Cross reservoir design or pressure spec.