DTC B2A16: Immobilizer Key Collation

Diagnosis start condition:

When ignition switch is ON.

DTC detecting condition:

When DCM received a remote request and couldn't detect valid cryptographic key within three seconds.

Trouble symptom:

RED LED ON

CAUTION:

After the DCM is replaced, registrations of CommCheck and immobilizer system are required. Ref. to ENTERTAINMENT & MONITORING>TELEMATICS SYSTEM>OPERATION>REGISTRATION (COMM CHECK)
Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to TELEMATICS SYSTEM (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION

CHECK DTC .
1. Turn the ignition switch to ON.
2. Read the DTC of [Telematics] using the Subaru Select Monitor. Ref. to TELEMATICS SYSTEM (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)
Is DTC B2A16 displayed? (Current code)

Yes : Go to 2.

No : Even if DTC is displayed, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

NOTE:
In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
CHECK DCM POWER SUPPLY .
Using the Subaru Select Monitor, check the following items in the [Data monitor] of [Telematics]. Ref. to TELEMATICS SYSTEM (DIAGNOSTICS)>DATA MONITOR
- Battery voltage
Is the voltage 9 - 16 V?

Yes : Go to 3.

No : Replace the battery and Go to 3.

Ref. to STARTING/CHARGING SYSTEMS (H4DOTC)>BATTERY>REMOVAL
PERFORM IMMOBILIZER SYSTEM RE-REGISTRATION .
Perform re-registration of immobilizer system for DCM using the Subaru Select Monitor. Refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.

NOTE:
"Telematics Control Module", which is described in "REGISTRATION MANUAL FOR IMMOBILIZER", is described as "DCM" in the service information.

Is registration complete?

Yes : Go to 4.

No : Refer to "Correspondence table when registration is not possible" in the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.
CHECK DTC .
Read the DTC of [Telematics] using the Subaru Select Monitor. Ref. to TELEMATICS SYSTEM (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

Is DTC B2A16 displayed? (Current code)

Yes : Replace the DCM. Ref. to ENTERTAINMENT & MONITORING>DATA COMMUNICATION MODULE

No : Immobilizer system for DCM is not registered. Function returned to normal.