hvac

AC Expansion Valve (TXV)

for 2021 Toyota RAV4 2.5L I4 · AWD

Difficulty

Advanced

Time

4.2 h

Tools

Steps

This procedure covers replacement of the AC expansion valve (TXV) on a 2019-2024 Toyota RAV4 with 2.5L I4 engine, requiring AC system evacuation, component removal, and refrigerant recharge.

Warnings

⚠️AC refrigerant can cause frostbite and eye injury. Wear safety glasses and gloves during all AC work.

⚠️Improper AC system service can damage components. Only proceed if you have proper AC recovery equipment and EPA certification.

⚠Never open AC system fittings without fully evacuating refrigerant. Environmental regulations prohibit venting refrigerant to atmosphere.

⚠Replace all AC line O-rings during reassembly to prevent leaks.

ℹ️The expansion valve is located at the evaporator inlet, behind the glove box assembly on this vehicle.

Tools required

AC recovery/evacuation/recharge machineEssential

Torque wrench (10-40 Nm range)Essential

Flare nut wrench setEssential

Socket set (10mm, 12mm, 14mm)

Ratchet and extensions

Trim removal tools

Shop towels or rags

UV leak detection dye kit

Digital thermometer

Safety glassesEssential

Parts

AC expansion valve (TXV) × 1 — 88719-42010 or equivalent
AC line O-rings × 4 — Use OEM specification
R-134a refrigerant × 1 — Check capacity label under hood
PAG oil (ND-11) × 1 — Toyota ND-11 compressor oil

Fluids

PAG oil (ND-11) — 0.17 qt

Preparation

Park vehicle on level surface and engage parking brake
Allow engine to cool completely if recently operated
Disconnect negative battery terminal and wait 90 seconds for airbag system discharge
Verify AC system refrigerant type (should be R-134a on 2019-2024 models)
Prepare clean workspace to place removed interior trim components

Procedure

1
Evacuate AC refrigerant
Connect AC recovery machine to service ports (low-side port on suction line, high-side on liquid line near condenser). Follow machine manufacturer instructions to fully recover all refrigerant from the system. Record amount recovered to verify correct recharge quantity later. Allow system to reach atmospheric pressure before disconnecting machine.
2
Remove glove box assembly
Open glove box and remove contents. Squeeze sides of glove box inward to release stoppers from frame, allowing box to drop fully open. Disconnect glove box light connector if equipped. Remove screws securing glove box hinge pins (typically 4 screws) and remove entire glove box assembly from vehicle. Set aside in safe location.
3
Access evaporator cover
Locate the evaporator housing on the passenger side behind the glove box opening. Remove the lower instrument panel cover by releasing clips and removing retaining screws. This exposes the evaporator housing access cover. You may need to remove the side trim panel for better access.
4
Remove evaporator access cover
Remove the screws securing the evaporator housing access cover (typically 4-6 screws around perimeter). Carefully pull cover away from housing. The expansion valve is now visible at the evaporator inlet where the liquid line enters the housing.
Torque spec
Cover Screws11 Nm (8 lb-ft)
5
Disconnect liquid line from expansion valve
Using a flare nut wrench, carefully loosen and remove the liquid line fitting from the expansion valve inlet. Support the expansion valve body with another wrench to prevent twisting. Plug line immediately with clean cloth or cap to prevent contamination. Remove and discard the old O-ring from the fitting.
6
Disconnect evaporator line from expansion valve
Using a flare nut wrench, loosen and remove the evaporator inlet line fitting from the expansion valve outlet. Again support the valve body to prevent damage. Plug opening immediately. Remove and discard old O-ring. Note the orientation of the expansion valve for correct installation of replacement.
7
Remove expansion valve
Remove the bolts or clips securing the expansion valve to the evaporator housing. The valve may be held by mounting brackets or directly bolted to the housing. Carefully extract the expansion valve assembly, noting the position of any insulation or clips. Inspect the mounting surface on evaporator for debris or damage.
8
Install new expansion valve
Position the new expansion valve in the same orientation as the original. Ensure any insulation wrapping or thermal sensing bulb (if external) is correctly positioned. Install mounting bolts or clips and torque mounting hardware to specification. Verify valve is secure and properly aligned with line fittings.
⚠If expansion valve has an external sensing bulb, ensure it makes proper thermal contact with the suction line as specified by manufacturer.
Torque spec
Expansion Valve10 Nm (7 lb-ft)
9
Connect evaporator line to expansion valve
Install new O-ring on evaporator line fitting. Lightly coat O-ring with ND-11 PAG oil (approximately 1-2 drops). Thread fitting onto expansion valve outlet by hand to ensure proper alignment. Tighten to specification using flare nut wrench while supporting valve body with backup wrench.
Torque spec
AC Line Fittings20 Nm (15 lb-ft)
10
Connect liquid line to expansion valve
Install new O-ring on liquid line fitting. Lightly coat O-ring with ND-11 PAG oil. Thread fitting onto expansion valve inlet by hand, then tighten to specification using flare nut wrench. Support valve body with backup wrench to prevent twisting or damage to evaporator connection.
Torque spec
AC Line Fittings20 Nm (15 lb-ft)
11
Reinstall evaporator access cover
Verify no tools or debris remain in evaporator housing. Position access cover onto housing, ensuring proper seal alignment. Install all cover screws and torque to specification in a cross-pattern to ensure even sealing.
Torque spec
Cover Screws11 Nm (8 lb-ft)
12
Reinstall interior components
Reinstall lower instrument panel covers and side trim panels, ensuring all clips are fully seated. Reinstall glove box assembly by positioning hinge pins and installing retaining screws. Reconnect glove box light if equipped. Test glove box operation and verify stoppers engage properly.
13
Vacuum and leak test AC system
Connect AC service machine to system. Evacuate system to full vacuum (29+ inches Hg) and hold for minimum 30 minutes. System should hold vacuum without pressure rise, indicating no leaks. If vacuum drops, locate and repair leak before proceeding. A proper vacuum also removes any moisture from the system.
⚠Insufficient vacuum time can leave moisture in system, leading to corrosion and compressor damage.
14
Recharge AC system
With system still under vacuum, recharge with refrigerant to quantity specified on underhood label (typically 400-500g for this model). Add appropriate amount of ND-11 PAG oil to compensate for oil lost during service (approximately 20-30ml total). If using UV dye for leak detection, add now per manufacturer instructions. Reconnect negative battery terminal.

Reassembly

All interior trim panels must be fully secured with clips properly seated to prevent rattles
Ensure glove box operates smoothly and stoppers engage without forcing
Verify no tools or parts were left in evaporator housing or interior area

Verification

Start engine and turn AC to maximum cold with fan on high
Allow system to run for 5-10 minutes, verify cold air from vents (typically 40-50°F at vent)
Check for unusual noises from compressor or evaporator area
Verify both AC lines show appropriate temperature differential (liquid line warm, suction line cold and sweating)
Inspect all AC fittings for signs of oil leakage using UV light if dye was added
Monitor system performance over next few days to ensure proper cooling and no refrigerant loss
Check cabin air filter condition and replace if needed for optimal airflow