Cannot Lock/Unlock With Keyless Access From The Driver's Door

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.

Trouble causes:

Malfunction of door lock control system
Malfunction of keyless access control module power supply circuit
Malfunction of harness between keyless access control module and front door outer handle
Keyless access control module malfunction
Malfunction of front door outer handle

Wiring diagram:

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

Courtesy of SUBARU OF AMERICA, INC.

CAUTION:

Check that there are no other registered access keys inside the vehicle.
Inspect LAN system according to the basic diagnostic procedure, and make sure that there is no fault.
Check that the keyless access function is not stopped.
When the keyless access control module is replaced, registration of the immobilizer is required. For the relevant procedures, 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 DOOR LOCK SWITCH .
Check that the lock/unlock operates with the driver's door lock switch.

Does it lock/unlock normally?

Yes : Go to 2.

No : Check the door lock circuit. Ref. to SECURITY AND LOCKS>DOOR LOCK CONTROL SYSTEM>INSPECTION
CHECK FUSE .
Check the fuse. Ref. to WIRING SYSTEM>KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM>WIRING DIAGRAM

Is the check result OK?

Yes : Go to 3.

No : Replace the fuse.
CHECK HARNESS .
1. Disconnect the connector from the keyless access control module.
2. Disconnect the connector from the front outer handle.
3. Using a tester, measure the resistance between the keyless access control module connector and front outer handle connector.
  Connector & terminal
  
  (i92) No. 5 - (Df36) No. 1:
  
  (i92) No. 6 - (Df36) No. 2:
Is the resistance less than 1 Ω?

Yes : Go to 4.

No : Repair or replace the open circuit of harness.
CHECK HARNESS (GROUND SHORT CIRCUIT) .
Using a tester, measure the resistance between the keyless access control module connector and chassis ground.

Connector & terminal

(i92) No. 5 - Chassis ground:

(i92) No. 6 - Chassis ground:

Is the resistance 10 kΩ or more?

Yes : Go to 5.

No : Repair or replace the short circuit of the harness.
CHECK KEYLESS ACCESS CONTROL MODULE .
1. Connect the keyless access control module connector.
2. Turn the ignition switch to OFF, close all doors and take the access key out of passenger room.
3. Using an oscilloscope, measure the waveform between front outer handle connectors.
  Connector & terminal
  
  (Df36) No. 1 - (Df36) No. 2:
Does pulse output change from no pulse output to pulse output detected when the lock operation using access key is performed?

Yes : Go to 6.

No : Replace the keyless access control module. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE>REMOVAL
REPLACE FRONT DOOR OUTER HANDLE .
Replace the driver's side front outer handle with the passenger's side front outer handle. Ref. to SECURITY AND LOCKS>DOOR OUTER HANDLE>REMOVAL

Does it operate properly?

Yes : Replace the driver's side front outer handle. Ref. to SECURITY AND LOCKS>DOOR OUTER HANDLE

No : Replace the keyless access control module. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE>REMOVAL