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 WRX BaseFACTORY OEM SERVICE PROCEDURE
Electrical Specification
WARNING: This page is about a different car, the 2022 Subaru WRX. However, it is still accessible from the selected car via links, so may be relevant.
| Connector No. | Terminal No. | Contents | Measuring condition | Standard |
|---|---|---|---|---|
| B76 | 1 | Ground | Always Measurement between (B76) No. 1 - (B76) No. 2 |
10 - 16 V |
| B76 | 2 | Battery power supply | ||
| B77 | 1 | Ignition power supply | Ignition switch: ON Measurement between (B77) No. 1 - (B76) No. 1 |
9 - 16 V |
| B77 | 2 | Advanced safety CAN_H signal | Digital signal; cannot be measured | - |
| B77 | 3 | Advanced safety CAN_L signal | Digital signal; cannot be measured | - |
| B77 | 5 | Chassis CAN_L signal | Digital signal; cannot be measured | - |
| B77 | 6 | Chassis CAN_H signal | Digital signal; cannot be measured | - |
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:
- • 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.