Parts for your 2012 Toyota Crown-Radiator cap

2012 Toyota Crown radiator cap — purpose, care, and when to replace

Referencing Toyota’s own technical materials, the 2012 Toyota Crown does use a radiator cap. The Toyota Crown (S200/S210 series) factory repair manual includes “Radiator Cap Sub–Assembly—Inspection” under the Cooling System section, and the Toyota Electronic Parts Catalogue lists a “Radiator Cap Sub‑Assembly (1.1)” for 2012 Crown variants (typical part refs: 16401‑31650 / 16401‑31670, rated 108 kPa). Those official sources confirm the radiator cap is relevant and fitted to this model.

On the 2012 Crown, the radiator cap is a small but critical bit of kit. It seals the cooling system and holds a set pressure (about 108 kPa / 1.1 bar), which lifts the coolant’s boiling point so the engine can run cool under load and in hot conditions. The cap’s two-way valve lets expanding coolant move into the overflow bottle as things heat up, then draws it back into the radiator as the engine cools, keeping air out and the system topped up. A tired cap can cause hard-to-pinpoint dramas like gradual overheating, coolant loss, and hoses that collapse as the engine cools.

As part of regular servicing, it’s smart to have the cap checked at the same time as coolant level and condition. Under‑bonnet checks should include the cap’s rubber seal for nicks or flattening, the spring for good resistance, and the neck for clean seating. Given the Crown runs Toyota Super Long Life Coolant, many owners pair cap replacement with coolant service intervals (Toyota schedules SLLC at long intervals, but the cap should still be inspected at every service). If any doubt, fit a new quality 1.1 bar cap—genuine or OEM‑equivalent—to match the factory spec.

Handy tips for Crown owners:

• Never remove the cap when hot—wait until the upper radiator hose is cool to the touch.
• Look for white/pink crust around the cap or neck—often a sign of weeping or pressure loss.
• If hoses keep going flat after cooling, the vacuum valve in the cap may be done.
• Stick with the correct pressure rating, a lower or higher rating can invite overheating or leaks.

Keeping a healthy radiator cap on the 2012 Toyota Crown is a low‑cost way to protect the head gaskets, water pump, and radiator, and to keep long‑haul reliability right on song.

Popular questions about 2012 Toyota Crown radiator caps

What pressure rating should the radiator cap be?
Most 2012 Crown variants use a 108 kPa (1.1 bar) cap, as noted in Toyota service literature and EPC listings for the Radiator Cap Sub‑Assembly. Always confirm against the under‑bonnet label or the owner’s manual for the exact engine grade.

Where is the radiator cap on a 2012 Crown?
It’s typically on the top tank of the radiator, slightly offset from centre. Some engine variants may position the pressure cap on a separate filler neck near the engine outlet, with a non‑pressurised overflow bottle alongside. The expansion bottle cap isn’t the pressure cap.

How often should the radiator cap be replaced?
There’s no strict mileage rule, it’s condition‑based. Have it inspected at every service and replace if the seal is flattened or cracked, the spring feels weak, or there are signs of staining or coolant loss. Many owners refresh the cap around major cooling‑system services or at 5–7 years / 100,000–150,000 km as cheap insurance.