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.
Inspection Mode 5
| DTC | Description & trouble part | Note |
|---|---|---|
| B1A0C | FRONT RELAY CONTROL MODULE CAN REGISTER STUCK | - |
| U0074 | CONTROL MODULE COMMUNICATION BUS "BODY-CAN" OFF | - |
| U0122 | LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE | - |
| U0140 | LOST COMMUNICATION WITH BODY CONTROL MODULE | - |
| U0416 | INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE | - |
| U0422 | INVALID DATA RECEIVED FROM BODY CONTROL MODULE | - |
Diagnostic procedure:
- Using the Subaru Select Monitor, perform the clear memory of [Front Relay Control Module]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY
- Using the Subaru Select Monitor, read the DTC of [Front Relay Control Module] to check that there is no DTC displayed. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) NOTE:
If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis for the displayed DTCs. After solving the DTC, repeat from step 1 .
- Turn the ignition switch OFF → ON, and wait for 10 seconds or more.
- Using the Subaru Select Monitor, read the DTC of [Front Relay Control Module] to check that there is no DTC displayed. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) NOTE:
If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis for the displayed DTCs.
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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.
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