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.
2021 Subaru Ascent BaseFACTORY OEM SERVICE PROCEDURE
Remote Control Mirror Switch: Inspection
- Check the resistance between switch door mirror terminals.
Preparation tool:
Circuit tester
- Changeover switch, right side (model without electric retractable mirror)
Terminal No. Inspection conditions Standard 12- 1
12.- 18OFF 1 MΩ or more 12- 18
17- 1UP Less than 1 Ω 12- 17
18- 1DOWN Less than 1 Ω 12.- 16
18- 1LEFT Less than 1 Ω 12- 18
16- 1RIGHT Less than 1 Ω - Changeover switch, left side (model without electric retractable mirror)
Terminal No. Inspection conditions Standard 12- 1
12- 21OFF 1 MΩ or more 12- 20
21- 1DOWN Less than 1 Ω 12- 21
20- 1UP Less than 1 Ω 12- 19
21- 1LEFT Less than 1 Ω 12- 21
19- 1RIGHT Less than 1 Ω - Changeover switch, right side (model with electric retractable mirror)
Terminal No. Inspection conditions Standard 12- 1
12- 21OFF 1 MΩ or more 12- 21
17- 1UP Less than 1 Ω 12- 17
21- 1DOWN Less than 1 Ω 12- 16
21- 1LEFT Less than 1 Ω 12- 21
16- 1RIGHT Less than 1 Ω - Changeover switch, left side (model with electric retractable mirror)
Terminal No. Inspection conditions Standard 12- 1
12- 21OFF 1 MΩ or more 12- 20
21- 1DOWN Less than 1 Ω 12- 21
20- 1UP Less than 1 Ω 12- 19
21- 1LEFT Less than 1 Ω 12- 21
19- 1RIGHT Less than 1 Ω - Folding switch (model with electric retractable mirror)
Terminal No. Inspection conditions Standard 12- 5
4. 1Retraction Less than 1 Ω 12- 4
5- 1Unfolding Less than 1 Ω - If the inspection result is not within the standard value, replace the switch assembly power window main.
Factory Service Tools
Use the Manual With the Right Hardware
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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.