Parts for your 2011 Mazda Cx-5-Tx valve

2011 Mazda CX-5 TX valve — what it does and when to service it

Based on technical sources, the 2011-build Mazda CX-5 (KE series, launched late 2011 for the 2012 model year) runs a thermostatic expansion valve, often called a TX valve. The Mazda CX-5 (KE) Workshop Manual HVAC section lists an “Expansion Valve” mounted at the evaporator, and the Mazda Electronic Parts Catalogue for the KE series carries the part under Heating and Air Conditioning. DENSO air‑conditioning service literature also notes TX valves are paired with variable-displacement compressors like those used in the CX-5, which matches the system layout on this model.

On this CX-5, the TX valve meters how much liquid refrigerant enters the evaporator, reacting to evaporator outlet temperature and pressure. That keeps vent temps stable, cabin humidity in check, and stops the evaporator icing up. Because it constantly balances flow in Aussie and Kiwi stop‑start traffic, a healthy TX valve is a big part of why the CX-5’s A/C feels consistent on hot days.

There’s no scheduled replacement interval for a TX valve. It’s serviced on condition. Tell‑tales of a tired or sticking valve include weak cooling at idle, vents that swing from too cold to lukewarm, frost on the evaporator pipes, or pressure readings that are out of whack on the gauges. Cabin filter blockages can make symptoms worse, so keeping that filter fresh helps the system behave.

If replacement is needed, it’s a straightforward but licensed job. The valve sits at the firewall where the A/C lines bolt to the evaporator block. A technician will recover the R134a, swap the TX valve and O‑rings, torque to spec, vacuum the system thoroughly, then recharge to the exact weight. It’s smart practice to renew the receiver‑drier desiccant (integrated with the condenser on this generation) any time the system’s opened, and to add the correct PAG oil quantity for any parts changed. Expect roughly 1.5–3 hours depending on access and corrosion on fittings.

To keep the CX-5’s A/C happy: run it weekly year‑round to circulate oil, wash the condenser face to clear bugs and road grime, replace the cabin filter on time, and have pressures and vent temps checked if cooling performance changes. With those basics sorted, the TX valve usually lives a long, quiet life.

• Common signs of TX valve trouble: erratic vent temps, poor idle cooling, frosty lines, abnormal pressure readings.
• Best practice on replacement: new O‑rings, vacuum and recharge, and renew the drier/desiccant.

Popular questions

Does a 2011 Mazda CX-5 use a TX valve or an orifice tube?
The KE-series CX-5 uses a thermostatic expansion valve at the evaporator, not an orifice tube. This is shown in the Mazda CX-5 Workshop Manual HVAC assembly diagrams and the Mazda EPC parts listing.

Where is the TX valve on a 2011 CX-5 and how long does it take to replace?
It’s mounted at the firewall on the evaporator inlet and outlet block. Access is from the engine bay. With proper refrigerant recovery and recharge, most workshops allow around 1.5–3 hours.

Should the drier be replaced when changing the TX valve?
Yes, recommended. The receiver‑drier is integrated with the condenser on this model. Renewing the desiccant helps protect the new valve and compressor from moisture and debris.