Parts for your 2020 Mazda Cx-5-Tx valve

2020 Mazda CX-5 TX‑Valve: What it is, why it matters, and how to look after it

Technical sources including the Mazda CX‑5 (KF, 2017–2021) Workshop Manual HVAC section, the Mazda Electronic Parts Catalogue for CX‑5 (KF) listing an “Expansion Valve,” and Denso A/C service data as referenced in professional databases (e.g., Mitchell1 and ALLDATA) confirm the 2020 Mazda CX‑5 is fitted with a thermostatic expansion valve (TXV) at the evaporator inlet. A TX‑valve is therefore relevant to this model.

On the 2020 Mazda CX‑5, the TX‑valve is the metering brain of the air‑con. It regulates how much liquid refrigerant enters the evaporator, using a sensing bulb and internal spring to maintain the right superheat. That clever metering keeps the evaporator cold without flooding the compressor, so cabin temps stay steady and the system doesn’t cop liquid slugging under hard Aussie and Kiwi summer loads.

Working with the variable‑displacement Denso compressor and the factory‑specified refrigerant and oil, the TX‑valve balances low‑ and high‑side pressures for efficient cooling at idle and on the motorway. When it sticks or goes out of calibration, owners notice weak cooling at stops, icy vents that then swing hot, or frost on the evaporator pipes near the firewall.

A TX‑valve isn’t a routine service item, but it deserves attention during A/C work. During scheduled air‑con servicing or any component replacement:

• Recover and recharge by weight, not pressure.
• Replace the O‑rings at the valve block and pipe joints, and lubricate with the correct oil.
• If the system has seen a compressor failure or metal contamination, replace the condenser/drier, flush appropriate lines, and fit a new TX‑valve to avoid repeat dramas.
• Leak‑test with dry nitrogen and vacuum‑hold before recharging.

Access on the CX‑5 is at the evaporator connection close to the firewall. Depending on workshop setup, cowl trims or nearby components may need moving, but it’s typically not a full dash‑out job. A tech will torque the valve fasteners correctly, evacuate the system, recharge to the stickered capacity, and verify superheat and vent temps.

Looking after the rest of the system helps the TX‑valve do its thing:

• Keep the condenser clean and straight.
• Renew the cabin filter on schedule so airflow across the evaporator is spot on.
• Run the A/C regularly to keep seals and the valve in good nick, summer and winter.

Get those basics right and the CX‑5’s TX‑valve quietly delivers crisp, consistent cooling for many kilometres. Odd gauge readings, rapid cycling, or a hiss at the valve under the cowl can also point to a sticky TXV, a licensed A/C tech will confirm with gauges and temp probes.

Popular questions about 2020 Mazda CX‑5 TX‑valves

Does the 2020 Mazda CX‑5 use a TX‑valve or an orifice tube?
It uses a thermostatic expansion valve (TXV) mounted at the evaporator connection. This setup gives finer control of superheat and more stable vent temperatures than a fixed orifice tube arrangement.

When should the TX‑valve be replaced?
It’s not a scheduled replacement item. Replace it if there are symptoms of sticking or restriction, after a compressor failure with debris, or when contamination/moisture is found. A proper diagnosis with gauges and temperature checks is the go.

Is TX‑valve access a dash‑out job on the CX‑5?
Typically, no. Access is near the firewall at the evaporator connection. Workshops may need to move cowl trims or adjacent components, but it’s generally handled in‑bay without removing the dashboard.