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 B1A00: Front Relay Control Module Non-Volatile Memory
DTC detecting condition:
- When the access (write) result to the Data Flash is abnormal.
- When the access (read) result to the Data Flash is abnormal.
- When the read data is abnormal.
Trouble symptom:
-
Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION
- CHECK DTC
.
- Turn the ignition switch to ON.
- Read the DTC of [Front Relay Control Module] using the Subaru Select Monitor. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)
Is DTC B1A00 displayed? (Current code)
Yes : Go to 2.
No : Temporary access error occurred to the flash memory.
- CHECK CONNECTOR
.
- Turn the ignition switch to OFF.
- Disconnect the connector from the front relay control module.
- Connect the disconnected connectors.
- Turn the ignition switch to ON.
- Read the DTC of [Front Relay Control Module] using the Subaru Select Monitor. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)
Is DTC B1A00 displayed? (Current code)
Yes : Replace Front relay control module. Ref. to BODY CONTROL/COMMUNICATION SYSTEM>FRONT RELAY CONTROL MODULE
No : Temporary EEPROM access error occurred.
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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.
