Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Check THERMO Control Valve Assembly
- CHECK THERMO CONTROL VALVE ASSEMBLY
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- Using the Subaru Select Monitor, select [Coolant Circulation Valve Control] of [Active Test].NOTE: For detailed operation procedures, refer to the "Active Test". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>ACTIVE TEST .
- Adjust the target value of [Coolant Circulation Valve Control] to set the value of [Coolant Circulation Valve Target Angle] to 79 deg.
- Read the value of [Coolant Circulation Valve Actual Angle].
Is the value of [Coolant Circulation Valve Actual Angle] between 73.7 deg - 84.3 deg within seven seconds after setting [Coolant Circulation Valve Target Angle]?
Yes: Go to 2 .
No: Replace the thermo-control valve assembly. Ref. to Cooling (H4DO)>Thermo Control Valve Assembly .
- Using the Subaru Select Monitor, select [Coolant Circulation Valve Control] of [Active Test].
- CHECK THERMO CONTROL VALVE ASSEMBLY
.
- Adjust the target value of [Coolant Circulation Valve Control] to set the value of [Coolant Circulation Valve Target Angle] to -83 deg.
- Read the value of [Coolant Circulation Valve Actual Angle].
Is the value of [Coolant Circulation Valve Actual Angle] between -77.7 deg - -88.3 deg within seven seconds after setting [Coolant Circulation Valve Target Angle]?
Yes: The thermo control valve assembly is in a normal condition. Perform other inspections.
No: Replace the thermo-control valve assembly. Ref. to Cooling (H4DO)>Thermo Control Valve Assembly .
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.