Power Will Not Turn On (Accessory Does Not Turn On, But Ignition Turns On)

Trouble causes:

Keyless access control module power supply circuit failure
Relay failure
Push button ignition switch circuit failure

CAUTION:

When the keyless access control module is replaced with a new unit, and the battery ground terminal is connected, it will become ignition ON. Also, if the battery is disconnected, it will resume to a condition with the battery cut off.
For replacement procedure of keyless access control module, refer to the "REGISTRATION INSTRUCTIONS FOR IMMOBILIZER" provided as a separate volume.
Before performing diagnosis, refer to "CAUTION" in "General Description". Refer to KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .

Wiring diagram:

Push button start system. Refer to WIRING SYSTEM>PUSH BUTTON START SYSTEM>WIRING DIAGRAM .

Engine type: FA

Courtesy of SUBARU OF AMERICA, INC.
Engine type: EJ

Courtesy of SUBARU OF AMERICA, INC.

CHECK FUSE.
Check the fuse. Refer to SECURITY AND LOCKS>RELAY AND FUSE>INSPECTION .

Is the check result OK?

Yes: Go to 2.

No: Replace the fuse.
CHECK CONNECTOR.
Check the engagement of each connector and terminal for any deformation or looseness.

Is the check result OK?

Yes: Go to 3.

No: Repair the connector, or replace harness.
CHECK HARNESS (OPEN CIRCUIT).
1. Disconnect the keyless access control module connector.
2. Using a tester, measure the voltage between the keyless access control module connector and chassis ground.
  Connector & terminal
  
  (B573) No. 1 (+) - Chassis ground (-):
  
  (B573) No. 4 (+) - Chassis ground (-):
  
  Is the voltage between 8 V and 16 V?
  
  Yes: Go to 4.
  
  No: Repair or replace the open circuit of harness.
CHECK HARNESS (OPEN CIRCUIT).
Using a tester, check continuity between the keyless access control module connector and chassis ground.

Connector & terminal

(B573) No. 20 - Chassis ground:

(B574) No. 17 - Chassis ground:

Is there continuity?

Yes: Go to 5.

No: Repair or replace the open circuit of harness.
CHECK ACCESSORY RELAY (PUSH BUTTON START).
Check the accessory relay (push button start). Refer to SECURITY AND LOCKS>RELAY AND FUSE .

Is the check result OK?

Yes: Go to 6.

No: Replace the relay.
CHECK HARNESS (OPEN CIRCUIT).
1. Disconnect the keyless access control module connector and the accessory relay (push button start).
2. Using a tester, check continuity between the keyless access control module connector and accessory relay (push button start).
  Connector & terminal
  
  (B573) No. 16 - (B426) No. 1:
  
  Is there continuity?
  
  Yes: Go to 7.
  
  No: Repair or replace the open circuit of harness.
CHECK HARNESS (GROUND SHORT CIRCUIT).
Using a tester, check continuity between the keyless access control module connector and chassis ground.

Connector & terminal

(B573) No. 16 - Chassis ground:

Is there continuity?

Yes: Repair or replace the short circuit of the harness.

No: Go to 8.
CHECK KEYLESS ACCESS control module.
1. Connect the keyless access control module connector.
2. Using a tester, measure the voltage between the keyless access control module connector and chassis ground when the ignition is turned from OFF to ON.
  Connector & terminal
  
  (B573) No. 16 (+) - Chassis ground (-):
  
  Did the voltage change from 1 V or less →+B-2 V or more?
  
  Yes: 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.
  
  No: Replace the keyless access control module. Refer to SECURITY AND LOCKS>KEYLESS ACCESS control module .