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.
DTC C1431 At: Trouble Symptom
2016 Subaru Legacy 2.5iSECTION Trouble Symptom
- VDC does not operate.
- Hill hold does not function.
- EyeSight does not operate. (Models with EyeSight)
DIAGNOSTIC PROCEDURE
| Step | Check | Yes | No |
|---|---|---|---|
1 CHECK TCM.
|
Is DTC displayed? | Perform the diagnosis according to DTC. < Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) . > | Go to step 2 . |
2 CHECK VDCCM & H/U.
|
Is the same DTC displayed? | Replace the VDCCM & H/U. < Ref. to VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM & H/U) . > | Go to step 3 . |
| 3 CHECK DETECTION OF OTHER DTCS FOR VDC. < Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) . > |
Is any other DTC displayed? | Perform the diagnosis according to DTC. < Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) . > | Currently, it is normal. There may have been a poor contact in the harness and connector or a temporarily noise interference. |
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.