Parts for your 2014 Mazda Cx-5-Radiator cap

Radiator cap on a 2014 Mazda CX-5

For the 2014 Mazda CX‑5, a traditional radiator cap on the radiator itself isn’t used. Mazda’s factory documentation shows the CX‑5 runs a sealed cooling system that places the pressure cap on the coolant reservoir (expansion tank), not on the radiator. This is clear from the Mazda CX‑5 Owner’s Manual (cooling system/engine coolant section) and the Mazda Workshop Manual procedures for engine coolant replacement, which direct technicians to open the reservoir cap and never mention a separate radiator filler cap. The Mazda electronic parts catalogue also lists a reservoir (expansion) tank cap for this model and no radiator‑mounted cap.

Why design it this way? It’s a modern layout that keeps the radiator as a closed unit without a filler neck. The pressurised cap on the expansion tank controls system pressure and coolant flow to and from the reservoir as temperatures change. It improves packaging under the bonnet, reduces the chance of scalding from a hot radiator neck, and makes servicing simpler because filling, bleeding, and pressure control all happen at the tank.

So, while searches for a “2014 Mazda CX‑5 radiator cap” are common, the relevant service item is actually the coolant reservoir pressure cap. If the CX‑5 is losing coolant, running hotter than normal, or building hoses that feel either collapsed or ballooned, a tired reservoir cap could be the culprit. The cap’s job is to hold a specific pressure so the coolant’s boiling point stays high, when its spring weakens or the rubber seal perishes, it can vent early, pull air into the system on cool‑down, or cause overflow.

For peace of mind in Aussie and Kiwi conditions, it’s smart to:

• Inspect the reservoir cap at each service for cracked plastic, a flattened or split rubber seal, and crusty coolant residue.
• Replace the cap if there’s any doubt, matching the pressure rating printed on the original cap and using quality OEM or equivalent parts.
• Only open the cap when the engine is stone cold, and refill with Mazda‑approved coolant mix to the FULL mark on the tank.

Bottom line: the 2014 CX‑5 doesn’t use a radiator‑mounted cap, it uses a pressure cap on the expansion tank, and that’s the part to check, maintain, or replace during cooling‑system service.

Popular questions

Does a 2014 Mazda CX‑5 have a radiator cap?
Not on the radiator itself. The system is sealed and uses a pressure cap on the coolant reservoir (expansion tank). That cap manages system pressure and replaces the old‑school radiator neck cap.

What cap do I need for my CX‑5 and what pressure rating is correct?
Use a genuine or high‑quality equivalent reservoir pressure cap that matches the pressure rating stamped on your current cap. Part numbers and ratings can vary by engine and market, so check the vehicle’s VIN against a Mazda parts catalogue or ask a dealer to confirm.

How do I top up coolant if there’s no radiator cap?
Top up via the coolant reservoir. When the engine is completely cold, remove the reservoir cap, fill to the FULL mark with Mazda‑approved coolant mix, refit the cap, then run the engine with the heater on hot to purge air. Recheck the level once cooled and adjust if needed.