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.

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:

CAUTION:

Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION

CHECK DTC .
1. Turn the ignition switch to ON.
2. 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 .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from the front relay control module.
3. Connect the disconnected connectors.
4. Turn the ignition switch to ON.
5. 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.

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.

Safety Warning

DTC B1A00: Front Relay Control Module Non-Volatile Memory

Use the Manual With the Right Hardware

When to See a Mechanic

Rather have a pro handle this?