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Home >> Subaru >> 2015 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Engine Mechanical >> Starter >> Entry Start System Entry System (Keyless Entry) >> Entry & Start System (Entry Function) >> Neither Smart Lock Nor Smart Unlock Operation Works On Any Of The Doors (Wireless Function Does Not Work Either) >> Inspection steps
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Inspection steps

CAUTION:
  • Some functions of the entry & start system (entry function) use the LIN communication system and the CAN communication system. Inspect the communication function by referring to "How to troubleshoot" (Refer to HOW TO PROCEED WITH TROUBLESHOOTING  ). Confirm that the communication system is functioning properly before proceeding to repair the entry & start system (entry function).
  • Before replacing the collation ECM (smart key ECM assembly), refer to "ENTRY & START SYSTEM (ENTRY FUNCTION) ". (Refer to )
  • Check if the electrical key transmitter sub-assembly is inside the vehicle.
  • Before proceeding with the inspection procedure, check that the DTC B1242 (wireless door lock control) is not output. (Refer to DTC CHECK/CLEAR  )
  • Before performing the following inspection steps, check the fuses related to this system.
  • Even if you want to check the entry lock operation several times, the setting does not allow you to perform the lock operation more than twice in a row. To perform the entry lock operation more than twice, you have to unlock a door once (you may use any type of unlock operation). This limitation applies only to the entry lock operation. A wireless lock or other types of lock operations can be performed any number of times without any limitations.
  • After the repair work is complete, perform the "DTC output check operation" to confirm that the DTC is not output again.
  • The door control receiver is supplied 5 volts of power from the collation ECM.
  1. Check the battery voltage.
    1. Measure the voltage of the vehicle battery.

      Standard voltage: 11 to 14V

      NOTE: You can check if the vehicle battery is discharged by operating the horn. If the voltage is 11V or less, charge or replace the vehicle battery before performing the operation.

      Next

  2. DTC check
    1. Using the mechanical key integrated into the electrical key transmitter sub-assembly, open the driver's door.
    2. Connect the SSM3 and check the DTC. (Refer to DTC CHECK/CLEAR  )

      Criteria: No DTC is output

      NG: Go to "LIST OF DIAGNOSTIC CODES " (Refer to ).

      OK: Go to next step

  3. Check the power door lock control system.
    1. Operate the door control switch on the driver's side power window regulator master switch assembly, and check if the door locks or unlocks properly according to the switch operation you have performed.

      Criteria: The door lock operation is performed properly.

      NG: Go to "Power door lock control system".

      OK: Go to next step

  4. Check the electrical key transmitter sub-assembly.
    1. Check if an electrical key transmitter sub-assembly registered to another vehicle is present.

      Result

      Result Go to
      An electrical key transmitter sub-assembly registered to another vehicle is not present. A
      An electrical key transmitter sub-assembly registered to another vehicle is present. B

      B: Go to Step  6.

      A: Go to next step

  5. Register a new electrical key transmitter sub-assembly.
    1. Register a new electrical key transmitter sub-assembly. (Refer to the "Registration manual for immobilizer")

      Next

  6. Check the entry door lock operation.
    1. Using another electrical key transmitter sub-assembly registered to the vehicle, check if an entry lock/unlock operation can be performed 2 or more times in a row.

      Criteria: The entry lock/unlock operation can be performed properly.

      NG: Go to Step  9.

      OK: Go to next step

  7. Check the transmitter battery.
    1. Check the transmitter battery level of the first electrical key transmitter sub-assembly checked.
      1. Hold down the lock switch on the transmitter for 5 seconds and check how many times the LED on the transmitter blinks.

      Result

      Result Go to
      The LED on the transmitter does not light up while the switch is held down. A
      The LED on the transmitter blinks 3 times while the switch is held down. B
      The LED on the transmitter blinks twice but not for the third time. C
      NOTE:
      • While in use, the electrical key transmitter sub-assembly transmits voltage information to the collation ECM (smart key ECM assembly). If the voltage is 2.4 V or lower, the collation ECM (smart key ECM assembly) displays [Yes] for [Key Low Battery] (an item under [Current Data Display & Save]). (Refer to DTC CHECK/CLEAR  )
      • To start the engine when the transmitter battery is drained, depress the brake pedal, hold down the engine switch, and place the electrical key transmitter sub-assembly over the engine switch.

      B: Replacement of the electrical key transmitter sub-assembly

      C: Replace the transmitter battery.

      A: Go to next step

  8. Inspect the transmitter battery unit (voltage).
    1. Remove the transmitter battery from the faulty electrical key transmitter sub-assembly. (Refer to TRANSMITTER BATTERY (WITH SMART ENTRY) )
    2. Using tape or the like, attach the lead wire (0.60 mm or less in diameter, including the wire sheath) to the negative terminal.
      CAUTION: Do not twist the lead wire around the terminal, tuck it into the terminal, or solder it to the terminal. If the terminal is deformed or damaged, the transmitter battery cannot be properly installed.
    3. Carefully pull the lead wire, and insert the previously removed transmitter battery.
    4. Measure the voltage of the transmitter battery.
      Fig 1: Measuring Transmitter Battery Voltage
      G10216251Courtesy of SUBARU OF AMERICA, INC.
      NOTE:
      • Measure the transmitter battery voltage by bringing the electrical key transmitter sub-assembly inside the lock entry operating range while operating the lock sensor on the door handle.
      • Perform this measurement when the key is at the room temperature.
      • During signal transmission, the key transmits voltage information to the collation ECM (smart key ECM assembly). If the voltage is 2.4 V or lower, [Yes] is displayed for [Key Low Battery] (an item under [Current Data Display & Save]). (Refer to DTC CHECK/CLEAR  )

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Switch conditions Specified condition
      Transmitter battery positive terminal (+) - transmitter battery negative terminal (-) Change the power mode to IG OFF, close all doors, and touch the lock sensor. 2.5 - 3.2V

      NG: Replace the transmitter battery.

      OK: Replacement of the electrical key transmitter sub-assembly

  9. Checking the waveform environment
    1. Move the electrical key transmitter sub-assembly towards the door control receiver and check that the wireless and entry functions work properly.
      NOTE:
      • Try moving the electrical key transmitter sub-assembly closer to the door control receiver, so that it is less likely to be affected by interference from external radio waves. In this way, you can identify if the problem is caused by external radio waves or not.
      • If this inspection reveals that the problem occurs in certain locations or during certain periods of time, the problem is likely due to interference from external radio waves. In addition, installing an additional component to the vehicle makes the vehicle more susceptible to interference from external radio waves. If such components are found, remove them, and then proceed to check the operation.
      • Being close to a broadcast antenna, a large video display, a wireless garage door opener system, a wireless security camera, or a home security system makes the vehicle susceptible to interference from external radio waves. If this is the case, move the vehicle to another location to check if the problem improves.
      • If a tool for checking radio waves such as a signal-strength meter is available, take measurements in the LF band (which is used by the vehicle antenna to create a detection area) and the RF band (which is used by the electrical key transmitter sub-assembly for signal transmission) in the vicinity of the vehicle to check where the radio waves might be present.

      Criteria: Both the wireless and entry functions work properly.

      NG: Go to Step 10.

      OK: Interference from external radio waves

  10. Read numerical values using the SSM3 ([ACC SW], [Ignition].
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM3.
    4. Enter the following menus: [Integ. unit mode] →[Current Data Display & Save]
    5. Based on the contents of the SSM3 display, read the [Current Data Display & Save].

      Main body

      MAIN BODY ITEM DESCRIPTION

      Tester display Measurement items/range Normal condition Notes for diagnosis
      [ACC SW] The engine switch is ON (ACC)/OFF or ON. OFF: The engine switch is OFF.
      ON: The engine switch is on (ACC).      		 -
      [Ignition] The engine switch is ON (IG)/[OFF] or [ON] OFF: The engine switch is OFF.
      ON: Engine switch is ON (IG)      		 -

      NG: Refer to the troubleshooting procedure for the main body ECM (Refer to HOW TO PROCEED WITH TROUBLESHOOTING  ).

      OK: Go to next step

  11. Check the harnesses and connectors (collation ECM (smart key ECM assembly) - battery and chassis ground).
    1. Disconnect the D48 collation ECM (smart key ECM assembly) connector.
    2. Measure the resistance according to the following table.

      Resistance

      RESISTANCE REFERENCE

      Inspection terminals Inspection conditions Standard value
      D48-11 (GND) - chassis ground Always 1 Ωor less
    3. Measure the voltage according to the following table.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      D48-2 (+B) - chassis ground Always 11 - 14 V
      Fig 2: Collation ECM (Smart Key ECM Assembly) Connector End View (D48)
      G10216252Courtesy of SUBARU OF AMERICA, INC.
    4. Reconnect the D48 connector of the collation ECM (smart key ECM assembly).

      NG: Repair or replace the harnesses or connectors.

      OK: Go to next step

  12. Check the harnesses and connectors (collation ECM - door control receiver).
    1. Disconnect the D40 collation ECM (smart key ECM assembly) connector.
    2. Disconnect the H28*1 or H26*2 door control receiver connector.
    3. Measure the resistance according to the following table.

      *1: With TPMS

      *2: Without TPMS

      Resistance

      RESISTANCE REFERENCE

      Inspection terminals Inspection conditions Standard value
      D40-5 (RCO) - H28-10 (RCO)(1)
      D40-5 (RCO) - H26-4 (+5)(2)      		 Always 1 Ωor less
      D40-17 (RDA) - H28-9 (DATA)(1)
      D40-17 (RDA) - H26-5 (DATA)(2)      		 Always 1 Ωor less
      D40-19 (RSSI) - H28-6 (RSSI)(1)
      D40-19 (RSSI) - H26-2 (RSSI)(2)      		 Always 1 Ωor less
      D40-5 (RCO) - chassis ground Always 10 kΩ or more
      D40-17 (RDA) - chassis ground Always 10 kΩ or more
      D40-19 (RSSI) - chassis ground Always 10 kΩ or more
      (1) With TPMS
      (2) Without TPMS

      NG: Repair or replace the harnesses or connectors.

      OK: Go to next step

  13. Inspect the door control receiver unit.
    1. Reconnect the H28*1 or H26*2 door control receiver connector.
    2. Measure the resistance according to the following table.

      Resistance

      RESISTANCE REFERENCE

      Inspection terminals Inspection conditions Standard value
      H28-12 (GND) - chassis ground(1)
      H26-1 (GND) - chassis ground(2)      		 Always 1 Ωor less
      (1) With TPMS
      (2) Without TPMS
      Fig 3: Door Control Receiver Connector Terminal Identification (H26, H28)
      G10216253Courtesy of SUBARU OF AMERICA, INC.
    3. Reconnect the D48 connector of the collation ECM (smart key ECM assembly).

      NG: Replace the door control receiver.

      OK: Go to next step

  14. Unit inspection of the collation ECM (smart key ECM assembly)
    1. Reconnect the D40 collation ECM (smart key ECM assembly) connector.
    2. Measure the voltage according to the following table. Resistance
      Inspection terminals Inspection conditions Standard value
      D48-11 (GND) - chassis ground Always 1 Ωor less
    3. Measure the voltage according to the following table.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      H28-10 (RCO) - H28-12 (GND)(1)
      H26-4 (+5) - H26-1 (GND)(2)      		 Procedure:
      1. The engine switch is OFF.
      2. The electrical key transmitter sub-assembly is not pressed.
      		 1 V or less
      Procedure:
      1. The engine switch is OFF.
      2. The electrical key transmitter sub-assembly is pressed.
      		 4.5 - 5.5V
      (1) With TPMS
      (2) Without TPMS
      Fig 4: Door Control Receiver Connector Terminal Identification (H26, H28)
      G10216254Courtesy of SUBARU OF AMERICA, INC.

      NG: Replacement of the collation ECM (smart key computer assembly)

      OK: Go to next step

  15. Inspect the door control receiver unit.
    1. Measure the voltage according to the following table.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      H28-6 (RSSI) - H28-12 (GND)(1)
      H26-2 (RSSI) - H26-1 (GND)(2)      		 Procedure:
      1. All doors are closed.
      2. All doors are locked.
      3. The electrical key transmitter sub-assembly is not pressed.
      		 11 - 14 V
      Procedure:
      1. All doors are closed.
      2. All doors are locked.
      3. The electrical key transmitter sub-assembly is pressed.
      		 2V or less
      H28-9 (DATA) - H28-12 (GND)(1)
      H26-5 (DATA) - H26-1 (GND)(2)      		 Procedure:
      1. All doors are closed.
      2. All doors are locked.
      3. The electrical key transmitter sub-assembly is not pressed.
      		 11 - 14 V
      Procedure:
      1. All doors are closed.
      2. All doors are locked.
      3. The electrical key transmitter sub-assembly is pressed.
      		 11 to 14 V →2 V or less →11 to 14 V, pulses generated at normal time intervals
      (1) With TPMS
      (2) Without TPMS
      Fig 5: Door Control Receiver Connector Terminal Identification (H26, H28)
      G10216255Courtesy of SUBARU OF AMERICA, INC.

      NG: Replace the door control receiver.

      OK: Go to next step

  16. Replacement of the collation ECM (smart key computer assembly)
    1. Temporarily replace the collation ECM (smart key ECM assembly) with a new one.
      CAUTION: When replacing the collation ECM (smart key ECM assembly), it is also necessary to replace all the electrical key transmitter subassemblies.

      Next

  17. Check the wireless door lock control system.
    1. Check that the wireless door lock function operates properly. (Refer to OPERATION CHECK )

      Criteria: The wireless door lock function operates properly.

      NG: Replace the main body ECM (multiplex network body ECM).

      OK: END (collation ECM (smart key ECM assembly) detected)

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