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Home >> Subaru >> 2019 >> BRZ Limited, Standard Trans >> Repair and Diagnosis >> Body & Frame >> Windows >> Glass & Power Window System >> Window Defogger System >> Window Defogger Does Not Operate >> Inspection steps
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Inspection steps

WARNING:
  • Window defogger system uses CAN communication. First, perform a "Communication function inspection", following "How to troubleshoot", and after checking for any malfunction in the communication system, you can proceed with troubleshooting.
  • Before performing the troubleshooting, check the fuse of this circuit.
  1. Implementation of SSM4 active test (Rr defogger output)
    1. Using SSM4, perform an [Active Test] by following the display.

      SSM4 screen: [Each System] → [Body Control] → [Active Test]

      Item name Contents of testing Constraints
      [Rear defogger] Rear defogger output ON/OFF -

      Result

      RESULT DESCRIPTION

      Result Go to
      Window defogger is not activated. A
      Window defogger is activated. B
      1. Go to next step
      2. Perform the circuit test shown on the symptom table. (Refer to SYMPTOM TABLE )
  2. Unit inspection of defogger relay (RR DEF relay)
    1. Perform unit inspection of the defogger relay (RR DEF relay). (Refer to RELAY )

      OK: Go to next step

      NG: Replacement of defogger relay (RR DEF relay)

  3. Inspection of wire harness and connector (defogger relay - IG 1 No. 1 relay and battery)
    1. Detach the defogger relay (RR DEF relay) from the engine compartment relay block.
    2. Measure the voltage between the terminals.

      Voltage

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      1 - Chassis ground IG ON 11 to 14 V
      3 - Chassis ground Always 11 to 14 V
      G12594961Courtesy of SUBARU OF AMERICA, INC.

      OK: Go to next step

      NG: Repair or replacement of wiring harness or connector

  4. Inspection of wire harness and connector (defogger relay - main body ECM (network gateway computer))
    1. Detach the defogger relay (RR DEF relay) from the engine compartment relay block.
    2. Disconnect the A73 connector of the main body ECM (network gateway computer).
    3. Measure the resistance between the terminals.

      Resistance

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      2 - A73-24 Always Less than 1 Ω
      2 - Chassis ground Always 10 kΩ or more

      Result

      RESULT DESCRIPTION

      Item Go to
      NG A
      OK (except for automatic air conditioning) B
      OK (for automatic air conditioning system) C
      1. Go to next step
      2. Go to Step  5.
      3. Go to Step  7.

      Repair or replacement of wiring harness or connector

  5. Inspection of wire harness and connector (main body ECM (network gateway computer) - heater control SUB-ASSY)
    1. Disconnect the connector D6 for the main body ECM (network gateway computer).
    2. Disconnect the connector D22 of the heater control SUB-ASSY.
    3. Measure the resistance between the terminals.

      Resistance (open circuit check)

      STANDARD VALUE SPECIFICATION

      Inspection terminals (Terminal symbol) Inspection conditions Standard value
      D6-5 - D22-2 (RDEF+) Always Less than 1 Ω

      Resistance (short circuit check)

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      D6-5 - Chassis ground Always 10 kΩ or more

      OK: Go to next step

      NG: Repair or replacement of wiring harness or connector

  6. Unit inspection of heater control SUB-ASSY (Rear defogger switch)
    1. Detach heater control SUB-ASSY (Rear defogger switch) (Refer to REMOVAL )
    2. Perform unit inspection of heater control SUB-ASSY (Rear defogger switch) (Refer to UNIT INSPECTION )

      OK: Go to next step

      NG: Replacement of rear defogger switch

  7. Inspection of wire harness and connector (back window glass - defogger relay and chassis ground)
    1. Disconnect the connectors G10 and H29 for the back window glass.
    2. Detach the defogger relay (RR DEF relay) from the engine compartment relay block.
    3. Measure the resistance between the terminals.

      Resistance (open circuit check)

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      G10-1 - 5 Always Less than 1 Ω

      Resistance (short circuit check)

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      G10-1 - Chassis ground Always 10 kΩ or more
      H29-1 - Chassis ground Always Less than 1 Ω

      OK: Go to next step

      NG: Repair or replacement of wiring harness or connector

      Replacement of the back window glass (Refer to REMOVAL )

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