Parts for your 2017 Honda Odyssey-Tx valve

2017 Honda Odyssey TX valve (thermal expansion valve)

Yes, the 2017 Honda Odyssey is fitted with TX valves. Technical sources confirm this: the Honda Odyssey 2011–2017 Service Manual (HVAC section) specifies a thermal expansion valve at each evaporator, Honda’s dealer parts catalogue lists “Valve Set, Expansion (Front)” and “Valve Set, Expansion (Rear)”, and independent repair databases such as ALLDATA and Mitchell 1 diagram the dual-evaporator layout with front and rear TX valves.

On this Odyssey, the TX valve meters refrigerant into the evaporator based on outlet temperature and pressure, keeping superheat in check so the air-con cools strongly without flooding the compressor. With front and rear air, there are two metering points: one near the front evaporator at the firewall, and another for the rear unit behind interior trim. When the valves are healthy, cabin temps stabilise quickly, demist is crisp, and the system avoids icing.

While TX valves aren’t a routine “service item”, they should be assessed whenever the system is opened, performance drops, or pressure readings are off. Typical triggers for replacement include contamination after a compressor failure, a stuck pintle causing low cooling at idle, or icing at the evaporator. Good workshop practice is to recover refrigerant properly, replace the valve(s) with new O-rings lubricated with the correct PAG oil, renew the receiver/drier or desiccant bag as specified for the Odyssey, evacuate to deep vacuum, and recharge to the exact charge shown on the under‑bonnet label. It’s also worth inspecting the cabin air filter and condenser face, airflow issues can mimic TX valve faults.

• Common signs of a crook TX valve on an Odyssey: warm air at stops but cooler on the move, vent temperature swings, frosting on lines near the firewall or rear quarter, hissing plus poor cooling, or unusual high/low gauge pressures.
• Because the Odyssey has both front and rear evaporators, a fault may only affect one zone. A scan tool that reads HVAC data and proper manifold gauges help pinpoint which valve is misbehaving.
• Torque fasteners to factory spec, use the correct O-ring sizes/colours, and always leak-test after re-gassing.

Look after the TX valves by keeping the system clean, dry, and correctly charged—simple habits that keep family road trips comfortably cool across Aussie and Kiwi summers.

Popular questions

Where is the TX valve on a 2017 Honda Odyssey?
The front TX valve sits at the front evaporator near the firewall in the engine bay area, the rear TX valve is mounted at the rear evaporator, typically behind the right-side rear interior trim. Access to the rear unit involves removing interior panels, while the front usually requires under‑bonnet access and some HVAC line work.

What symptoms point to a failing TX valve on this model?
Expect slow or uneven cooling, vent temps that swing hot–cold, frosting at the evaporator lines, and odd gauge readings (very low suction or unusually high head pressure). On dual‑zone Odysseys, one zone may cool poorly while the other seems fine, which helps narrow down which valve is at fault.

Should the drier or desiccant be replaced when changing a TX valve?
Yes, best practice is to replace the receiver/drier or desiccant bag whenever the system is opened or a valve is replaced. This helps remove moisture and debris that can damage the new valve and compressor. Always evacuate and recharge to the exact spec shown on the vehicle’s label.