This procedure covers the removal and replacement of the heater control valve on a 2019-2024 Toyota RAV4 with the 2.5L I4 engine, which regulates coolant flow to the heater core.

Warnings

Tools required

Parts

• Heater control valve × 1 — Use OEM specification
• Coolant hose clamps × 2 — 90467-07164 or equivalent

Fluids

• Toyota Super Long Life Coolant (Pink) — 2 qt

Preparation

1. Ensure engine is completely cool to the touch
2. Park vehicle on level ground and engage parking brake
3. Place drain pan beneath the engine
4. Remove engine cover by pulling upward on the four retention clips
5. Locate the heater control valve on the passenger side firewall area, below the cowl panel

Procedure

1. 1

   Drain cooling system partially
   Open the radiator drain cock located at the bottom passenger side of the radiator. Drain approximately 2 quarts of coolant into the drain pan. Close the drain cock once coolant level drops below the heater control valve position. This minimizes coolant loss during valve replacement.
   ⚠Coolant may still drip from hoses during removal even after partial drain. Keep drain pan positioned appropriately.
2. 2

   Disconnect electrical connector
   Press the locking tab on the heater control valve electrical connector and pull straight out to disconnect. On 2019-2021 models, the connector is gray; 2022-2024 models use a black connector. Do not pull on wires.
3. 3

   Release inlet hose clamp
   Locate the spring-type hose clamp on the inlet coolant hose (upper connection). Using hose clamp pliers or flathead screwdriver, compress or pry the clamp and slide it back along the hose approximately 2 inches away from the valve fitting. Note the orientation of the clamp for reinstallation.
4. 4

   Release outlet hose clamp
   Locate the hose clamp on the outlet coolant hose (lower connection). Release the clamp using the same method as the inlet and slide it back along the hose away from the valve fitting.
5. 5

   Remove coolant hoses
   Twist each coolant hose gently back and forth while pulling to break the seal and remove from the heater control valve fittings. Have shop towels ready to catch residual coolant. Place hose ends in an elevated position or plug them to minimize further coolant loss.
   ℹ️If hoses are stubborn, use a gentle rocking motion. Do not pry against the valve body as this may damage mounting points.
6. 6

   Remove valve mounting bolts
   Remove the two mounting bolts securing the heater control valve to the bracket on the firewall using a 10mm socket. Support the valve with one hand while removing the second bolt to prevent it from falling.
   Torque spec

   Valve Mounting8 Nm (6 lb-ft)
7. 7

   Remove heater control valve
   Carefully extract the heater control valve from the engine bay. Tilt as needed to clear surrounding components. Inspect the mounting bracket for damage or corrosion and clean the mounting surface with a shop towel.
8. 8

   Prepare new valve and hoses
   Inspect coolant hose ends for cracks, hardening, or deterioration. Replace hoses if any damage is present. Verify the new heater control valve matches the original in connector orientation and mounting hole positions. Inspect hose fittings on new valve for any shipping damage.
9. 9

   Install new heater control valve
   Position the new heater control valve onto the mounting bracket, aligning the mounting holes. Install both mounting bolts finger-tight, then torque to specification in a cross-pattern. Ensure the valve body is properly seated against the bracket before final torque.
   Torque spec

   Valve Mounting8 Nm (6 lb-ft)
10. 10

    Connect coolant hoses
    Push the inlet hose (upper) firmly onto the inlet fitting of the heater control valve until it bottoms out. Repeat for the outlet hose (lower). Ensure each hose is fully seated on the fitting barbs with no gaps visible between hose and fitting base.
11. 11

    Secure hose clamps
    Slide the inlet hose clamp forward into position over the fitting. Position the clamp between 1/4 and 1/2 inch from the end of the fitting. If using new screw-type clamps, tighten to specification. Repeat for the outlet hose clamp. Ensure clamps are positioned over the hose bead area on the fitting.
    Torque spec

    Hose Clamps3 Nm (2 lb-ft)
12. 12

    Reconnect electrical connector
    Align the electrical connector with the heater control valve terminals and push firmly until the locking tab clicks into place. Tug gently on the connector to verify it is fully seated and locked.
13. 13

    Refill cooling system
    Add Toyota Super Long Life Coolant (pink) to the radiator and coolant reservoir to restore proper level. Fill the reservoir to the FULL mark (cold). Slowly pour coolant into the radiator until it reaches the filler neck. Install the radiator cap.
    ⚠Only use Toyota Super Long Life Coolant (pink). Do not mix with other coolant types or colors.
14. 14

    Bleed cooling system
    Start the engine and allow it to reach normal operating temperature with the heater set to maximum temperature and fan on high. Monitor coolant level in the reservoir and add coolant as needed. Run engine until the cooling fans cycle on and off at least once. Check for leaks around the heater control valve connections.
15. 15

    Final inspection and top-off
    After engine has cooled completely, recheck coolant level in the reservoir and add coolant to bring to the FULL mark if needed. Inspect all connections at the heater control valve for any signs of seepage or leaks. Wipe down the valve area and check again after a short test drive.

Reassembly

1. Reinstall the engine cover by aligning the clips and pressing down firmly until all four clips snap into place
2. Verify no tools or materials were left in the engine bay
3. Clean any coolant spills from the engine bay and surrounding components

Verification

• Start the engine and verify the heater produces warm air at all temperature settings
• Check that coolant reservoir level remains stable after reaching operating temperature
• Inspect heater control valve and all hose connections for any coolant leaks
• Verify no warning lights are illuminated on the instrument cluster
• Test heater operation in AUTO mode (if equipped with automatic climate control) to confirm valve responds to commands
• After first drive cycle, recheck coolant level when engine is cold and top off if necessary

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