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.
2020 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE
Main Relay: Inspection
- Check that the main relay has no deformation, cracks or other damages.
- Measure the resistance between main relay terminals.
Terminal No. Standard 1 and 2 1 MΞ© or more 3 and 4 130.4 - 230.8 Ξ© (when 20Β°C (68Β°F)) - Connect battery positive terminal to terminal No. 3 and battery ground terminal to terminal No. 4, and measure the resistance between the main relay terminals.
Terminal No. Standard 1 and 2 Less than 1 Ξ©
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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