Gen 3/Gen 3+ DCM COMMCHECK Procedures (15-324-25)

GEN 3/GEN 3+ DCM COMMCHECK PROCEDURES

TECHNICAL SERVICE BULLETIN

APPLICABILITY

2023-25MY Legacy & Outback

2023-25MY Impreza & Crosstrek

2025MY Forester

2024-25MY WRX

2023-25MY Ascent

INTRODUCTION

This Service Information Bulletin details a new procedure for conducting a CommCheck on vehicles equipped with a GEN 3/GEN 3+ DCM. If the CommCheck is not performed correctly after DCM replacement or during the PDI process, it may not complete successfully and revert to Factory Mode, causing the telematics system to be nonoperational. On most 25MY or later models, if the DCM reverts to factory mode at any point, you must perform the immobilizer registration after the CommCheck is complete.  Failure to perform the immobilizer registration will cause the remote start function to be nonoperational and eventually set DTC B2A16.

SERVICE PROCEDURE/INFORMATION

REMINDER:  Customer satisfaction and retention starts with performing quality repairs.

CommCheck During PDI: 

Step 1)  After turning the ignition switch on, check that the LEDs light up momentarily. This will confirm that the DCM has turned on; please allow at least 30 seconds for this to occur.

Step 2)  Check that the green LED is lit before performing CommCheck. If the LED status is not green, proceed to step 5

Step 3)  Press and hold the "i" button for over 2 seconds to start the CommCheck. The red and green LEDs will begin to flash.

Step 4) Depending on the LED status, perform the next step accordingly:

Both LEDs Flashing		CommCheck is in progress (Continue to wait)
Both LEDs Are OFF		CommCheck is complete (The vehicle is unsubscribed: CommCheck is complete)
Both LEDs Are Solid		CommCheck has failed (Please try again if the CommCheck continues to fail perform sets outline in If CommCheck Fails section)
Green LED Is ON		DCM is in Factory Mode (CommCheck is not complete and DCM is in Factory Mode)

Step 5)  If both LEDs are OFF this indicates the vehicle is unsubscribed and the CommCheck has completed. If both LEDs are Solid this indicates the CommCheck has failed, please turn the ignition switch off for 5 minutes. Then turn the ignition switch on, the LEDs should begin to blink indicating the CommCheck has restarted. If CommCheck continues to fail, please refer to the steps in the 'If CommCheck Continues to Fail' section.

CommCheck after DCM replacement: 

Step 1)  After turning the ignition switch on, check that the LEDs light up momentarily. This will confirm that the DCM has turned on; please allow at least 30 seconds for this to occur.

Step 2)  Press and hold the "i" button for over 2 seconds to start the CommCheck. The red and green LEDs will begin to flash.

Step 3)  Depending on the LED status, perform the next step accordingly:

Both LEDs Flashing		CommCheck is in progress (Continue to wait)
Both LEDs Are OFF		CommCheck is complete (The vehicle is unsubscribed: CommCheck is complete.)
Both LEDs Are Solid		CommCheck has failed (Please try again if the CommCheck continues to fail perform sets outline in If CommCheck Fails section)
Green LED Is ON		DCM is in Factory Mode or CommCheck is complete if vehicle has active subscription. (CommCheck is complete or the DCM is in Factory Mode)

Step 4)  If CommCheck completes perform the immobilizer Registration following the instructions found in Registration Manual for Immobilizer.

Step 5)  Using the Subaru Select Monitor please check the following PID "Subscription Status" and "Immobilizer Key Registration Status" in the telematics current data display. If either Unsubscribed or Subscribed is displayed for Subscription Status, the CommCheck was successful. If Factory Mode is displayed for Subscription Status, please retry CommCheck. If Registered is displayed for Immobilizer Key Registration Status the immobilizer registration was successful. If No Registration is displayed, please attempt immobilizer registration again. If both LEDs are Solid this indicates the CommCheck has failed, please turn the ignition switch off for 5 minutes. Then turn the ignition switch on, the LEDs should begin to blink indicating the CommCheck has restarted. If CommCheck continues to fail, please refer to the steps in the 'If CommCheck Continues to Fail' section.

If CommCheck Continues to Fail: 

Step 1)  If CommCheck fails, relocate vehicle and try again.

Step 2)  Confirm the signal strength with a telematics-equipped vehicle in close proximity. A signal strength of 23% is sufficient to complete the CommCheck.

Step 3)  If CommCheck still fails after relocating the vehicle and confirming adequate signal strength, refer to the December 22 TechTIPS on Starlink Telematics - Comm Check, Test Calls, Remote Services requests, and Failed calls and perform the steps outlined in December 2022 Tech TIPS Page 13. 

Step 4)  If CommCheck continues to fail, ensure there are no current telematics DTCs, confirm powers and grounds at DCM and the antenna is operating as designed, if this is confirmed true then replace the DCM perform CommCheck and immobilizer registration.

IMPORTANT REMINDERS: 

• SOA strongly discourages the printing and/or local storage of service information as previously released information and electronic publications may be updated at any time.
• Always check for any open recalls or campaigns anytime a vehicle is in for servicing.
• Always refer to STIS for the latest service information before performing any repairs.