Parts for your 2006 Toyota Vitz|yaris-Tx valve

2006 Toyota Vitz/Yaris TX Valve — What it is, where it lives, and how to look after it

Based on Toyota technical literature and parts catalogues for the XP90-series Vitz/Yaris (2005–2011), the air-conditioning system uses a thermal expansion valve (TXV), also listed as a “Cooler Expansion Valve” at the evaporator inlet. Toyota’s repair manual AC section details removal/installation of this valve, and Toyota/DENSO component catalogues specify a block-type TXV for this model. So yes — the 2006 Toyota Vitz/Yaris is fitted with a TX valve, not a fixed orifice tube.

The TX valve is the metering brain of the Yaris’s A/C system. It takes high-pressure liquid refrigerant from the condenser and meters just the right amount into the evaporator, responding to the outlet tube temperature and pressure. That feedback keeps evaporator superheat in the sweet spot, which means cold air at the vents without freezing the core. On the 2006 Vitz/Yaris, the TXV is a compact block mounted at the evaporator, inside the cabin behind the glovebox area.

If the cabin’s cooling is weak, uneven, or the system cycles oddly, a sticking or mis‑metering TXV is a usual suspect. Other symptoms include frosty lines at the firewall, hissing, or high/low pressure readings that don’t match ambient conditions during gauge testing. Because it’s a precision metering device, contamination from moisture or debris (often after a compressor failure) can upset it.

During servicing, a licensed A/C technician should handle anything that opens the system — it’s illegal to vent refrigerant in Australia and New Zealand. Good workshop practice for a TXV job on this model includes:

• Fully recover refrigerant, then remove the glovebox and access the HVAC case to reach the valve.
• Replace the TXV and all related O‑rings, lubricate new O‑rings with the correct A/C oil.
• If the system has been open or a compressor failed, flush lines (not the TXV or evaporator), fit a new desiccant (many Yaris models have a condenser with an integrated desiccant bag), and ensure everything is squeaky clean.
• Evacuate to deep vacuum, then recharge with the factory-specified R‑134a mass shown on the under‑bonnet label, using the compressor’s specified oil (commonly DENSO ND‑OIL 8/PAG 46 — confirm by VIN/label).

Most owners won’t need routine TXV replacement, it’s generally a “replace on fault” item. That said, if the A/C’s been open to air, if there’s sludge from a failed compressor, or if cooling is erratic despite a healthy charge and fans, a new TXV is cheap insurance for consistent, icy performance in Aussie and Kiwi summers.

Popular questions

Where is the TX valve on a 2006 Toyota Vitz/Yaris?
It’s mounted at the evaporator inlet inside the dash, typically accessed by removing the glovebox and trims. The two A/C pipes pass through the firewall to this block-style valve. A tech will recover the refrigerant before cracking those lines.

Can a sticky TX valve be cleaned, or should it just be replaced?
Cleaning is hit-and-miss and rarely lasts. Because debris and moisture cause most TXV faults, replacement with new O‑rings is the reliable fix. If contamination is present, the condenser desiccant and oil balance should be addressed at the same time.

What refrigerant and oil does the 2006 Yaris use after a TX valve change?
From factory it uses R‑134a. Charge weight is shown on the under‑bonnet label and should be followed precisely. Use the compressor-specified oil (often DENSO ND‑OIL 8/PAG 46), added in the correct amount for the components changed. Always have a licensed A/C technician handle the recovery, vacuum, and recharge.