Parts for your 2020 Nissan Pathfinder-Tx valve

2020 Nissan Pathfinder TX valve: what it does and when to service or replace it

Yes, the 2020 Nissan Pathfinder is fitted with a TX valve (thermostatic expansion valve). Technical references that confirm this include the Nissan Factory Service Manual for the R52 platform (Heating & Air Conditioning/HA section), which specifies a block-type expansion valve at the front evaporator, and aftermarket technical catalogues from major A/C suppliers (e.g., DENSO and Four Seasons) that list direct-fit A/C expansion valves for the 2020 Pathfinder. Variants with rear air-conditioning use a second (rear) expansion valve at the auxiliary evaporator, so there may be one or two TX valves depending on spec.

The TX valve’s job is to meter refrigerant into the evaporator based on temperature and pressure, keeping superheat in the sweet spot. That means cold air at the vents without freezing the core, stable cabin temps for the tri‑zone climate control, and less risk of liquid slugging the compressor. When the valve sticks, wears out, or clogs with debris or desiccant, the air-con can run warm at idle, cycle temperatures, or ice up the evaporator.

As part of regular servicing of a 2020 Pathfinder’s air-con, the TX valve isn’t a routine replacement item, but it should be assessed whenever the system is opened or if there are performance complaints. Good practice includes:

• Checking for symptoms: weak cooling at low speed, fluctuating vent temps, hissing at the dash, frosty lines, or abnormal high/low-side pressures on gauges.
• Inspecting for contamination: metal debris or sludge suggests broader system issues—address the root cause, not just the valve.
• Replacing the receiver/drier and all disturbed O-rings whenever the circuit is opened, then evacuating and recharging to the exact under‑bonnet spec.
• If equipped with rear A/C, verifying both TX valves operate correctly—faults can hide in the rear unit.

Replacement is a licensed job in AU/NZ—refrigerant must be recovered, the system opened with care, the valve torqued to spec, then vacuumed and re-gassed. A clogged or mis‑metering TX valve won’t be fixed by a “re‑gas” alone, it needs proper diagnosis with temperature and pressure readings. Keeping the cabin filter fresh, the condenser clean, and the system leak‑free goes a long way to avoiding TX valve grief and keeps the Pathfinder’s air-con cooling hard through long summer kilometres.

Does the 2020 Pathfinder have one or two TX valves?
Most models have a front TX valve at the dash evaporator. Versions with rear air-conditioning include a second valve at the rear evaporator. If the vehicle has tri‑zone controls with an auxiliary rear unit, expect two.

What are the signs the TX valve is on the way out?
Common clues are warm air at idle, vent temperatures that swing hot-cold, frost on the evaporator or lines, and odd pressure readings. A noisy compressor or rapid cycling can also point to metering issues—testing with gauges and a thermometer confirms it.

Can a simple re‑gas fix a bad TX valve?
No. A re‑gas restores charge but won’t free a sticking or blocked valve. If the TX valve is faulty—or there’s contamination—proper repair involves component replacement, new O‑rings and drier, evacuation, and a precise recharge by a licensed tech.