Parts for your 2020 Toyota C-hr-Radiator cap

2020 Toyota C‑HR radiator cap — what’s actually fitted under the bonnet

On the 2020 Toyota C‑HR there isn’t a traditional radiator-mounted cap. Instead, the cooling system uses a sealed, pressurised expansion tank (reservoir) with a pressure cap on that tank. So, a “radiator cap” as older cars had isn’t used on this model.

That’s not just workshop folklore. Toyota’s 2020 C‑HR Owner’s Manual (AUS/NZ editions) directs owners to check and top up coolant at the reservoir only, and warns against opening the system when hot—there’s no separate radiator filler cap to remove. The Toyota Repair Manual for the AX10/AX50 series likewise shows a reservoir‑type, pressurised cooling system, and parts catalogues for the C‑HR list a pressure cap for the reserve/expansion tank rather than a radiator cap. Together, those technical sources confirm the design used on this vehicle.

Why did Toyota move away from a radiator cap on the radiator itself? It’s a modern, efficiency‑driven layout that offers a few wins:

• Safety: Keeping the pressure cap on a high‑mounted tank reduces the chance of scalds from hot coolant right at the radiator.
• Better air purge: A high point tank helps trap and bleed air, improving cooling performance and making bleeding after service more reliable.
• Packaging: With compact front ends and sloped bonnets, there’s rarely space for a safe, accessible radiator filler neck.
• Service simplicity: Owners and techs check and fill at one place—the reservoir—while the system stays sealed under normal conditions.

For servicing a 2020 C‑HR, attention shifts to the reservoir cap. It’s the pressure valve that controls system boiling point and return flow. During routine services, it’s smart to inspect the cap’s rubber seal and spring, check for staining or crusting around the neck (a hint of seepage), and make sure it tightens smoothly. Many workshops can pressure‑test the cap and system with an adaptor for the reservoir. If the cap is damaged, the seal is perished, or it can’t hold the specified pressure (often around 1.1 bar/108 kPa—confirm on the cap label or via service data for your VIN), replace it. Always use coolant that meets Toyota Super Long Life Coolant spec, never open the cap when hot, and bleed the system per Toyota’s procedure after any cooling-system work.

Popular questions

Does the 2020 Toyota C‑HR have a radiator cap?
No. It uses a sealed, pressurised expansion tank with its own pressure cap. The radiator itself doesn’t have a separate cap under the bonnet.

Where does coolant get topped up on a 2020 C‑HR, and what cap pressure does it use?
Coolant is checked and topped at the translucent expansion tank. The pressure rating is shown on the tank’s cap, many C‑HRs use roughly 1.1 bar (108 kPa), but always match what’s printed on your cap or in the factory data.

Should the 2020 C‑HR’s coolant cap be replaced as routine maintenance?
There’s no fixed replacement interval in Toyota’s schedule. Inspect it at each service—replace if the seal is cracked, the spring’s weak, there’s evidence of seepage, or it fails a pressure test. Using the correct spec cap is important for proper cooling and reliability.