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DTC C2303: Short in Power Source Relay Circuit [06/2015 - ]: Procedure

  1. CHECK SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT CONTROL ACTUATOR ASSEMBLY POWER SOURCE CIRCUIT) 
    1. Disconnect the shift control actuator assembly connector.
    2. Measure the voltage according to the value(s) in the table below.
      GTY571643Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Shift Control Actuator Assembly)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      D8-2 (BMA) - Body ground Power switch off Below 1 V
    3. Reconnect the shift control actuator assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  3

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL ECU ASSEMBLY - SHIFT CONTROL ACTUATOR ASSEMBLY) 
    1. Disconnect the transmission control ECU assembly connector.
    2. Disconnect the shift control actuator assembly connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY589910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Transmission Control ECU Assembly)
      *b Front view of wire harness connector
      (to Shift Control Actuator Assembly)

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      A25-5 (MUA) or D8-1 (MUA) - Body ground and other terminals Power switch off 10 kΩ or higher
      A25-2 (MVA) or D8-6 (MVA) - Body ground and other terminals Power switch off 10 kΩ or higher
      A25-1 (MWA) or D8-7 (MWA) - Body ground and other terminals Power switch off 10 kΩ or higher
    4. Reconnect the shift control actuator assembly connector.
    5. Reconnect the transmission control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE TRANSMISSION CONTROL ECU ASSEMBLY. Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  3. INSPECT P CON RELAY (TRANSAXLE PARKING LOCK CONTROL RELAY) 
    1. Remove the P CON relay (transaxle parking lock control relay) from the No. 3 motor compartment relay block.
      GTY596412Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 P CON relay (Transaxle Parking Lock Control Relay)
    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. Install the P CON relay (transaxle parking lock control relay).

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE P CON RELAY (TRANSAXLE PARKING LOCK CONTROL RELAY) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL ECU ASSEMBLY - P CON RELAY (TRANSAXLE PARKING LOCK CONTROL RELAY)) 
    1. Disconnect the transmission control ECU assembly connector.
    2. Remove the P CON relay (transaxle parking lock control relay) from the No. 3 motor compartment relay block.
    3. Measure the resistance according to the value(s) in the table below.
      GTY579304Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Transmission Control ECU Assembly)

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      A25-23 (BMA) - Body ground and other terminals Power switch off 10 kΩ or higher
    4. Install the P CON relay (transaxle parking lock control relay).
    5. Reconnect the transmission control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ACTUATOR ASSEMBLY - P CON RELAY (TRANSAXLE PARKING LOCK CONTROL RELAY)) 
    1. Disconnect the shift control actuator assembly connector.
    2. Remove the P CON relay (transaxle parking lock control relay) from the No. 3 motor compartment relay block.
    3. Measure the resistance according to the value(s) in the table below.
      GTY571644Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Shift Control Actuator Assembly)

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      D8-2 (BMA) - Body ground and other terminals Power switch off 10 kΩ or higher
    4. Install the P CON relay (transaxle parking lock control relay).
    5. Reconnect the shift control actuator assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  ELECTRONIC CIRCUIT INSPECTION PROCEDURE [06/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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