Parts for your 2009 Toyota Ractis-Radiator cap

Radiator cap for a 2009 Toyota Ractis

Based on Toyota’s own technical literature, the 2009 Toyota Ractis does use a radiator cap (pressure cap). The Toyota Electronic Parts Catalog (EPC) for Ractis models NCP100/NCP105 lists a “Cap Sub-Assy, Radiator” under PNC 16401 as an applicable service part. Toyota’s Repair Manual for the Ractis (Cooling section) also includes an “On-Vehicle Inspection – Radiator Cap” procedure covering seal condition and valve opening pressure checks, and the owner’s manual cautions against opening the radiator cap when hot. Those sources confirm a conventional pressurised cooling system with a serviceable radiator cap, either on the radiator filler neck or at a dedicated filler housing.

On a 2009 Ractis, the radiator cap quietly does a lot of heavy lifting. It seals the cooling system, holds a set pressure so the coolant’s boiling point sits safely higher, and manages expansion and contraction as the engine heats and cools. When things get hot under the bonnet, the cap allows excess pressure and coolant to flow to the overflow bottle. As it cools, the vacuum valve in the cap draws coolant back so the system stays topped up and free of air. If the cap gets tired — weak spring, perished rubber, sticky valve — the car can lose coolant, run hotter than it should, or end up with collapsed hoses.

As part of regular servicing, it’s smart to give the radiator cap some attention:

• Inspect the rubber seals for cracks or hardening, and check the neck for corrosion or debris.
• Pressure-test the cap with a cooling-system tester to confirm it opens at the specified kPa rating printed on the cap.
• Replace the cap if there’s any doubt — they’re inexpensive insurance against overheating.
• Match the exact pressure rating for the Ractis engine variant, using the wrong rating can cause leaks or premature hose/radiator failure.
• Only remove the cap when the engine is completely cold. Wrap a rag around it and open slowly.

When fitting a new cap, clean the filler neck, confirm the overflow hose is clear and tight, and ensure it locks firmly. Pair that with the correct Toyota Super Long Life Coolant (pink), and check the cap condition at every service. Given many 2009 vehicles are well into their middle age, swapping an original cap pre-emptively is a sensible move — especially before summer or a long holiday trip across Australia or New Zealand.

Popular questions about the 2009 Toyota Ractis radiator cap

What pressure rating radiator cap does a 2009 Ractis use?
The cap rating varies by engine and market, commonly around 88–108 kPa (0.9–1.1 bar). The correct rating is printed on the existing cap. If it’s unreadable, check by VIN in the Toyota EPC or ask a parts specialist to match the exact specification.

How often should the radiator cap be replaced?
Have it inspected at every service and pressure-tested during coolant changes. Many owners replace the cap preventively every 5–7 years or at the first sign of seal wear, erratic temperature behaviour, or unexplained coolant loss.

Can the Ractis be driven with a faulty radiator cap?
It’s not recommended. A dodgy cap can cause overheating, coolant loss, or hose collapse. If symptoms point to the cap, sort it before driving any distance to avoid bigger repair bills.