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Home >> Toyota >> 2012 >> Prius Four >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 119 (Smart Key System (For Entry Function) (Plug-In) (Diagnostic Codes & Symptom Tests)) >> SMART KEY SYSTEM (for Entry Function) >> Symptom Tests >> Back Door Entry Unlock Function does not Operate >> Procedure
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Back Door Entry Unlock Function does not Operate: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. READ VALUE USING TECHSTREAM (ENTRY BACK DOOR OPEN FUNCTION) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Key / Data List.
    5. Read the Data List according to the display on the Techstream.
      SMART KEY (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      B-Dr Opening Operation Back door opening Operation / Long, Twice, OFF Customization status displayed -

      Result

      Result Proceed to
      Customize setting is Long or Twice. A
      Customize setting is OFF. B

    B → See step   11 

    A: Go to next step 

  2. CHECK POWER DOOR LOCK OPERATION 
    1. When the door control switch on the master switch assembly is operated, check that the doors unlock and lock according to switch operation. Refer to OPERATION CHECK .

      OK

      Door locks operate normally.

    NG → See step   10 

    OK: Go to next step 

  3. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Enter the following menus: Body Electrical / Main Body / Active Test.
    2. Perform the Active Test according to the display on the Techstream.
      MAIN BODY (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

      Tester Display Test Part Control Range Diagnostic Note
      Trunk and Back-Door Open Operate back door lock motor ON or OFF -

      OK

      The back door lock assembly unlatches when ON is selected.

    NG → See step   10 

    OK: Go to next step 

  4. READ VALUE USING TECHSTREAM (BACK DOOR OPENER SWITCH) 
    1. Enter the following menus: Body Electrical / Smart Key / Data List.
    2. Read the Data List according to the display on the Techstream.
      SMART KEY (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Tr/B-Door Unlock SW Back door opener switch assembly (opener switch) / ON or OFF ON: Back door opener switch assembly (opener switch) pushed
      OFF: Back door opener switch assembly (opener switch) not pushed
      -

      OK

      On the Techstream screen, the display changes between ON and OFF as shown in the table above.

    NG → See step   6 

    OK → See step   5 

  5. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL 
  6. INSPECT BACK DOOR OPENER SWITCH ASSEMBLY 
    1. Remove the back door opener switch assembly. Refer to REMOVAL .
      Fig 1: Inspecting Back Door Opener Switch Assembly
      GTY224913Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Position Specified Condition
      2 (E) - 3 (UL) Back door opener switch assembly (opener switch) not pushed (OFF) 10 kΩ or higher
      2 (E) - 3 (UL) Back door opener switch assembly (opener switch) pushed (ON) Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Back Door Opener Switch Assembly)

    NG → See step   9 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - BACK DOOR OPENER SWITCH) 
    1. Disconnect the certification ECU (smart key ECU Assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      L62-22 (TSW5) - V4-3 (UL) Always Below 1 Ω
      L62-22 (TSW5) - Body ground Always 10 kΩ or higher
      V4-3 (UL) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   8 

  8. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL 
  9. REPLACE BACK DOOR OPENER SWITCH ASSEMBLY. Refer to  REMOVAL 
  10. GO TO POWER DOOR LOCK CONTROL SYSTEM (Proceed to Problem Symptoms Table). Refer to  PROBLEM SYMPTOMS TABLE 
  11. PERFORM CUSTOMIZE SETTING (Proceed to Customize Parameters). Refer to  CUSTOMIZE PARAMETERS