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DTC C2303: Short in Power Source Relay Circuit: Procedure

  1. CHECK SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT CONTROL ACTUATOR ASSEMBLY POWER SOURCE CIRCUIT) 
    1. Disconnect the D2 shift control actuator assembly connector.
    2. Measure the voltage according to the value(s) in the table below.
      Fig 1: Checking D2 Connector Terminals
      GTY291021Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      D2-2 (BMA) - Body ground Power switch off Below 1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Shift Control Actuator Assembly)
    3. Connect the D2 shift control actuator assembly connector.

    NG → See step   3 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL ECU ASSEMBLY - SHIFT CONTROL ACTUATOR ASSEMBLY) 
    1. Disconnect the A23 transmission control ECU assembly connector.
    2. Disconnect the D2 shift control actuator assembly connector.
    3. Measure the resistance according to the value(s) in the table below.
      Fig 2: Checking A23 & D2 Connector Terminals
      GTY341831Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A23-5 (MUA) or D2-1 (MUA) - Body ground and other terminals Power switch off 10 kΩ or higher
      A23-2 (MVA) or D2-6 (MVA) - Body ground and other terminals Power switch off 10 kΩ or higher
      A23-1 (MWA) or D2-7 (MWA) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Transmission Control ECU Assembly)
      *b Front view of wire harness connector
      (to Shift Control Actuator Assembly)
    4. Connect the D2 shift control actuator assembly connector.
    5. Connect the A23 transmission control ECU assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   6 

  3. INSPECT P-CON MTR RELAY (TRANSAXLE PARKING LOCK CONTROL RELAY) 
    1. Remove the P-CON MTR relay (transaxle parking lock control relay) from the engine room relay block and junction block assembly.
      Fig 3: Identifying P CON Mtr Relay (Transaxle Parking Lock Control Relay) Connector Terminals
      GTY293965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 - 5 Auxiliary battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      Auxiliary battery voltage is applied between terminals 1 and 2 Below 1 Ω
    3. Reinstall the P-CON MTR relay (transaxle parking lock control relay).

    NG → REPLACE P-CON MTR RELAY (TRANSAXLE PARKING LOCK CONTROL RELAY) 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL ECU ASSEMBLY - P-CON MTR RELAY) 
    1. Disconnect the A23 transmission control ECU assembly connector.
    2. Remove the P-CON MTR relay (transaxle parking lock control relay) from the engine room relay block and junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.
      Fig 4: Checking A23 Connector Terminals
      GTY326118Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A23-23 (BMA) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Transmission Control ECU Assembly)
    4. Reinstall the P-CON MTR relay (transaxle parking lock control relay).
    5. Connect the A23 transmission control ECU assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ACTUATOR ASSEMBLY - P-CON MTR RELAY) 
    1. Disconnect the D2 shift control actuator assembly connector.
    2. Remove the P-CON MTR relay (transaxle parking lock control relay) from the engine room relay block and junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.
      Fig 5: Checking Harness & Connector (Shift Control Actuator Assembly - P CON MTR Relay)
      GTY291023Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      D2-2 (BMA) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Shift Control Actuator Assembly)
    4. Reinstall the P-CON MTR relay (transaxle parking lock control relay).
    5. Connect the D2 shift control actuator assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   7 

  6. REPLACE TRANSMISSION CONTROL ECU ASSEMBLY. Refer to  COMPONENTS 
  7. CHECK FOR INTERMITTENT PROBLEMS. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
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