Harman Audio / Infotainment: Troubleshooting USB Functionality Concerns – 2017-2019 Subaru

NUMBER: 15-226-18R
DATE: 08/21/18
REVISED: 09/05/18

APPLICABILITY: 2017-2019MY Impreza
2018-19MY Crosstrek
2018-19MY Legacy and Outback
2019MY WRX and WRX STI
2019MY Ascent
2018-19MY BRZ
SUBJECT: Harman Audio / Infotainment: Troubleshooting USB Functionality Concerns



This bulletin provides troubleshooting steps to follow when diagnosing customer concerns regarding USB functionality.  Please start by completing the Harman Investigation Guide Questionnaire as it gathers important details which will help with diagnosis and will be required should the condition not be resolved by this troubleshooting.  While completing the questionnaire, follow the question flow based on the customer concern.   Answer each related question noting the results to each in detail while performing the diagnostics.  Review the entire bulletin before beginning in order to understand the flow for the listed concern.  If the concern you have is not listed, check the Service Manual “Infotainment (Diagnostics) – Diagnostics with Phenomena” section as a starting point.



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

1) Always confirm the condition as reported by the customer.

2) This section addresses USB detection symptoms.

a. Confirm the USB is recognized (USB icon appears) on the Media screen as shown in the figure below.

Confirm the USB is recognized (USB icon appears)


b. If the USB is not recognized, follow Service Diagnostic Mode from the Service Manual:

i. Turn the ignition switch to ACC.

ii. Press the “TUNE/SCROLL” button six times while pressing the “HOME” button.



i. On Service Menu, press “Connection” to display the list of items.

ii. OK: Each device is connected properly.

iii. NG: Connection is not established, or connection status (possibly including the related harness) is faulty.


  • The USB connection showing “NG” when no USB device is connected to USB ports is normal.
  • If the concern involves “CarPlay not working”, make sure a genuine Apple cable is used. In some cases, aftermarket cables may cause connection issues.
  • If the concern involves “Android Auto not working”, try using another cable since Android phones do not require use of a genuine cable.

USB connection

c. Do other USB devices work in the suspect vehicle? If yes, check the USB device’s operation in another like vehicle.

d. Please provide detailed information regarding the USB device (brand, device type, file system, types of files on device, etc.).

3) This section addresses issues related to Apple CarPlay and/or Android Auto not launching consistently due to poor connectivity to USB Media. Affected models and head units are:

New firmware was released during late 2017 to enhance connectivity for Auxiliary Terminal part numbers: 86257FL00A and 86257FL101 (MID, HIGH).

NOTE: The BASE model utilizes a different Auxilliary Terminal part number which is not affected.

How to determine if the Auxiliary Terminal is pre- or post-countermeasure (CM):

  • CAREFULLY peel off the QR code / part number label.
  • Check the Lot# as shown below. If the number is after “7411” it is post-CM.

Auxiliary Terminal

4) If the above steps do not resolve the customer’s concern with USB functionality, complete a fresh Harman Investigation Guide Questionnaire documenting the customer’s concern and the results of each diagnostic step in this bulletin. If possible, capture a video of the condition then contact the SOA Techline to review the next steps.  Techline will request you send the completed questionnaire, step-by-step bulletin test results and any videos of the condition.



For vehicles within the Basic New Car Limited Warranty period or covered by an active Subaru Added Security Gold plan, this repair may be submitted using the following claim information:

Labor Description Labor Operation # Labor
HARMAN USB TROUBLESHOOTING A850-873 0.5 ZLI-43 Base, Mid & High



  • 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.

NUMBER: 15-226-18R
REVISED: 09/05/18



Download (PDF, 539KB)

NUMBER: 15-226-18
DATE: 08/21/08



Download (PDF, 539KB)


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