DTC B278D: Id Code Box Judgment Circuit: Wiring diagram

Keyless access with push button start system. Ref. to WIRING SYSTEM>KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM>WIRING DIAGRAM .

G13228999

Courtesy of SUBARU OF AMERICA, INC.

CAUTION:

For replacement procedure of keyless access Control Module, refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.
Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to KEYLESS ACCESS WITH PUSH BUTTON START (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .

CHECK DTC .
1. Turn the ignition switch to OFF.
2. Using the Subaru Select Monitor, perform the clear memory of [Keyless Access with Push Button Start]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
3. Turn the ignition switch to OFF → ON.
4. Read the DTC of [Keyless Access with Push Button Start] using the Subaru Select Monitor. Ref. to KEYLESS ACCESS WITH PUSH BUTTON START (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is DTC B278D displayed? (Current malfunction)

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 HARNESS .
1. Disconnect the keyless access Control Module connector.
2. Measure the resistance between keyless access Control Module connector and chassis ground.
Connector & terminal

(i75) No. 18 - Chassis ground:

Is the resistance less than 1 Ω?

Replace the keyless access Control Module. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE .

Repair or replace the short circuit of the harness.