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Inspection Mode 8

WARNING: This page is about a different car, the 2021 Subaru Ascent. However, it is still accessible from the selected car via links, so may be relevant.
DTC Item Note
U0101 LOST COMMUNICATION WITH TCM BIU detects DTC only when [MT/AT Setting] is [AT].
U0128 LOST COMMUNICATION WITH PARK BRAKE CONTROL MODULE BIU detects DTC only when [EPB setting] is [Support].
U0164 LOST COMMUNICATION WITH HVAC CONTROL MODULE BIU detects DTC only when [Auto A/C Setting] is [Support].
U0169 LOST COMMUNICATION WITH SUNROOF CONTROL MODULE BIU detects DTC only when [Sunroof setting] is [Support].
U0208 LOST COMMUNICATION WITH "SEAT CONTROL MODULE A" BIU detects DTC only when [Seat Memory Setting] is [Support].
U0222 LOST COMMUNICATION WITH DRIVER'S DOOR POWER WINDOW BIU detects DTC only when [P/W ECU Setting] is [Driver Seat], [Driver/Passenger Seat] or [Four Seat].
U0223 LOST COMMUNICATION WITH PASSENGER'S DOOR POWER WINDOW BIU detects DTC only when [P/W ECU Setting] is [Driver/Passenger Seat] or [Four Seat].
U0224 LOST COMMUNICATION WITH RR DOOR POWER WINDOW BIU detects DTC only when [P/W ECU Setting] is [Four Seat].
U0225 LOST COMMUNICATION WITH RL DOOR POWER WINDOW BIU detects DTC only when [P/W ECU Setting] is [Four Seat].
U0230 LOST COMMUNICATION WITH REAR GATE MODULE BIU detects DTC only when [Power rear gate setting] is [Support].
U0231 LOST COMMUNICATION WITH RAIN SENSING MODULE BIU detects DTC only when [Rain drop Detection Sensor Setting] is [Support].
U0402 INVALID DATA RECEIVED FROM TCM BIU detects DTC only when [MT/AT Setting] is [AT].
U0417 INVALID DATA RECEIVED FROM PARK BRAKE CONTROL MODULE BIU detects DTC only when [EPB setting] is [Support].
U0424 INVALID DATA RECEIVED FROM HVAC CONTROL MODULE BIU detects DTC only when [Auto A/C Setting] is [Support].
U1235 LOST COMMUNICATION WITH EyeSight BIU detects DTC only when [High Beam Assist Function Setting (mirror/EyeSight)] is [EyeSight HBA].
U1433 INVALID DATA RECEIVED FROM EyeSight BIU detects DTC only when [High Beam Assist Function Setting (mirror/EyeSight)] is [EyeSight HBA].
U1673 LIN COMMUNICATION BUS ERROR BODY CONTROL MODULE BIU detects DTC only when any of the following customize settings is established:
  • [Rain drop Detection Sensor Setting] is [Exist]
  • [Power rear gate setting] is [Exist]
  • [Seat Memory Setting] is [Exist]
  • [Sunroof setting] is [Exist]
  • [Sunshade ECU Setting] is [Exist]
U1674 LIN COMMUNICATION BUS 2 ERROR BODY CONTROL MODULE BIU detects DTC only when [P/W ECU Setting] is [Driver Seat], [Driver/Passenger Seat] or [Four Seat].
U1769 LOST COMMUNICATION WITH SUNSHADE CONTROL MODULE BIU detects DTC only when [Sunshade ECU Setting] is [Exist].
U1822 LOST COMMUNICATION WITH MASTER MAIN SWITCH BIU detects DTC only when [P/W ECU Setting] is [Driver Seat], [Driver/Passenger Seat] or [Four Seat].

Diagnostic procedure:

  1. Using the Subaru Select Monitor, perform the clear memory of [Body Control]. Ref. to COMMON (diag)>CLEAR MEMORY .
  2. Using the Subaru Select Monitor, read the DTC of [Body Control] to check that there is no DTC displayed. Ref. to BODY CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC) .
    NOTE: If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis for the displayed DTCs. After solving the DTC, repeat from step  1). Ref. to BODY CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .
  3. Confirm that [Customize] items of [Body Control] correspond to the vehicle. Ref. to BODY CONTROL (DIAGNOSTICS)>CUSTOMIZE .
  4. Turn the ignition switch OFF → ON, and wait for 10 seconds or more.
  5. Using the Subaru Select Monitor, read the DTC of [Body Control] to check that there is no DTC displayed. Ref. to BODY CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC) .
    NOTE: If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis for the displayed DTCs. Ref. to BODY CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .