Parts for your 2019 Volkswagen Amarok-Tx valve

2019 Volkswagen Amarok TX valve: what it does and when to replace it

Based on Volkswagen factory workshop information (ErWin) for the Amarok 2H platform and common HVAC parts catalogues from Hella/Behr, Nissens and Four Seasons, the 2019 Volkswagen Amarok uses a thermostatic expansion valve (TX valve) at the evaporator. Those technical sources list a direct-fit expansion valve and outline remove-and-install procedures for the Amarok’s refrigerant circuit, confirming a TX valve is fitted rather than an orifice-tube setup.

The TX valve is the metering brain of the Amarok’s air-con. It regulates how much liquid refrigerant enters the evaporator, targeting a set superheat so the evaporator runs cold without letting liquid return to the compressor. That means quicker cool-down on a hot arvo, steady vent temps up steep climbs or at idle, and good compressor protection over big kilometres.

There’s no scheduled replacement for the TX valve, but it should be inspected whenever the system is open or performance drops. Typical clues it’s on the fritz include weak cooling at idle or at highway speeds, icing at the evaporator or lines, rapid cycling, uneven vent temps, or odd high/low-side pressure readings. Contamination from a failing compressor can also clog the valve’s tiny passages or stick its internals.

For replacement or deeper diagnosis, it’s a job for an ARCtick-licensed air-con technician. On the Amarok the valve sits at the evaporator on the HVAC housing, typically accessed by removing interior trim/glovebox components to reach the inlet and outlet block. Correct procedure is to recover the refrigerant, replace the valve and all related O-rings, and strongly consider renewing the receiver–drier (often integrated into the condenser). If the compressor has failed or debris is present, lines and the condenser should be flushed or replaced as recommended by the workshop manual and parts suppliers.

Recharging should be by weight to the label under the bonnet, with the correct oil type and quantity added. A deep vacuum and a pressure/leak check (nitrogen and trace dye, not just “top-ups”) help ensure the Amarok’s system stays leak-free and quiet. As part of routine servicing, keeping the cabin filter fresh and the condenser face clean will help the TX valve and the rest of the system do their best work across Aussie and Kiwi conditions.

• Watch for performance swings, icing or unusual pressure readings.
• Replace O-rings and drier whenever the system is opened.
• Recharge by weight with the refrigerant specified on the vehicle label.

Popular questions about the 2019 Volkswagen Amarok TX valve

Where is the TX valve located on a 2019 Amarok?
It’s mounted at the evaporator on the HVAC housing. Access is typically from inside the cabin by removing the glovebox and related trim to reach the evaporator inlet/outlet block. A licensed technician can confirm the exact access steps for the specific trim level.

What symptoms point to a faulty TX valve on an Amarok?
Common signs are poor cooling at idle or at highway speeds, fluctuating vent temperatures, icing on the evaporator or lines, hissing or hunting noises, and odd gauge readings (such as very low suction with normal/high head pressure). These can also be caused by low charge or a weak compressor, so proper diagnosis is key.

Should the TX valve be replaced when fitting a new compressor?
It’s often recommended, especially if the old compressor shed debris. At minimum, replace the receiver–drier and O-rings, flush where appropriate, and only skip the TX valve if it’s proven clean and responsive. This reduces the chance of repeat failures and protects the new compressor.