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Home >> Subaru >> 2015 >> 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, follow the "How to troubleshoot" and perform the "Communication function inspection" to check that malfunction does not occur in the communication system, and then proceed to the troubleshooting.
  • Before performing the troubleshooting, check the fuse of this circuit.
  1. Performing the SSM3 system operation check mode (R defogger output)
    1. Using SSM3, perform the [System Operation Check Mode] by following the display.

      SSM3 display: [Each System Check] →[Integ. unit mode] →[System Operation Check Mode]

      ITEM DESCRIPTION

      Item Name Contents of testing Constraints
      [Rr Defogger output] Rear defogger output ON / OFF -

      Result

      RESULT DESCRIPTION

      Result Go to
      Window defogger is not activated. A
      Window defogger is activated. B

      B: Perform the circuit test shown on the symptom table. (Refer to SYMPTOM TABLE  )

      A: Go to next step

  2. Unit inspection of defogger relay (RR DEF relay)
    1. Perform UNIT INSPECTION  of the defogger relay (RR DEF relay). (Refer to )

      NG: Replacement of defogger relay (RR DEF relay)

      OK: Go to next step

  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

      VOLTAGE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      1 - Chassis ground IG ON 11 to 14 V
      5 - Chassis ground Always 11 to 14 V
      Fig 1: Locating Defogger Relay (RR DEF Relay) On Engine Compartment Relay Block
      G10217483Courtesy of SUBARU OF AMERICA, INC.

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  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

      RESISTANCE 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

      B: Go to Step 5.

      C: Go to Step  7.

      A: Repair or replacement of wiring harness or connector

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

      Resistance (open circuit check)

      RESISTANCE (OPEN CIRCUIT CHECK)

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

      Resistance (short circuit check)

      RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

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

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

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

      NG: Replacement of rear defogger switch

      OK: Go to next step

  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)

      RESISTANCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      H29-1 - 5 Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

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

      NG: Repair or replacement of wiring harness or connector

      OK: Replacement of the back window glass (Refer to REMOVAL  )

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