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Home >> Lexus >> 2024 >> NX 250 FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 3 (Electronic A/T Shift Lever System - Diagnostic Codes & Circuit Tests) >> Electronic Shift Lever System >> DTC U0291-00: Lost Communication with Gear Shift Control Module "B" (System 2) Missing Message [11/2021 - ] >> Procedure

DTC U0291-00: Lost Communication with Gear Shift Control Module "B" (System 2) Missing Message [11/2021 - ]: Procedure

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  1. CHECK DTC OUTPUT (HEALTH CHECK) 

    Pre-procedure1

    1. Turn the ignition switch to ON.

      Procedure1

    2. Using the GTS, perform a Health Check.

      Result

      Result Proceed to
      U0291-00 only is output A
      U0291-00 and other DTCs are output B

      Post-procedure1

    3. Turn the ignition switch off.

    Result: 

    B 

    GO TO DTC CHART. Refer To  DIAGNOSTIC TROUBLE CODE CHART [11/2021 - ] 

    Result: 

    A 

    See step  2

  2. CHECK FOR SHORT IN CAN BUS LINE (ECU CONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.

      Procedure1

    2. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    3. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    NG 

    See step  6

    Result: 

    OK 

    See step  3

  3. CHECK FOR OPEN IN CAN BUS LINE (ECU CONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.

      Procedure1

    2. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) - D39-6 (CA3L) Cable from negative (-) auxiliary battery terminal disconnected 54 to 69 Ω

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    3. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  4

  4. CHECK FOR OPEN IN CAN BUS LINE (HYBRID VEHICLE CONTROL ECU DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the D67 hybrid vehicle control ECU connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) - D39-6 (CA3L) Cable from negative (-) auxiliary battery terminal disconnected 108 to 132 Ω

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the hybrid vehicle control ECU connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  5

  5. CHECK FOR OPEN IN CAN BUS LINE (BATTERY ECU ASSEMBLY DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the z14 battery ECU assembly connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) - D39-6 (CA3L) Cable from negative (-) auxiliary battery terminal disconnected 108 to 132 Ω

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the battery ECU assembly connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE BATTERY ECU ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  6. CHECK FOR SHORT IN CAN BUS LINE (SHIFT CONTROL ECU DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the D39 transmission floor shift assembly (shift control ECU) connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the transmission floor shift assembly (shift control ECU) connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE TRANSMISSION FLOOR SHIFT ASSEMBLY (SHIFT CONTROL ECU). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  7

  7. CHECK FOR SHORT IN CAN BUS LINE (HYBRID VEHICLE CONTROL ECU DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the D67 hybrid vehicle control ECU connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the hybrid vehicle control ECU connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  8

  8. CHECK FOR SHORT IN CAN BUS LINE (BATTERY ECU ASSEMBLY DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the z14 battery ECU assembly connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the battery ECU assembly connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE BATTERY ECU ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  9

  9. CHECK FOR SHORT IN CAN BUS LINE (SHIFT ACTUATOR ECU DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the B77 shift control actuator assembly (shift actuator ECU) connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the shift control actuator assembly (shift actuator ECU) connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  10

  10. CHECK FOR SHORT IN CAN BUS LINE (RADIO AND DISPLAY RECEIVER ASSEMBLY DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the D2 radio and display receiver assembly connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the radio and display receiver assembly connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  11

  11. CONFIRM VEHICLE SPECIFICATION 
    1. Choose the model to be inspected.

      Result

      Result Proceed to
      w/ Wireless Charger System A
      w/o Wireless Charger System B

    Result: 

    B 

    See step  13

    Result: 

    A 

    See step  12

  12. CHECK FOR SHORT IN CAN BUS LINE (MOBILE WIRELESS CHARGER CRADLE ASSEMBLY DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the d1 mobile wireless charger cradle assembly connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the mobile wireless charger cradle assembly connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE MOBILE WIRELESS CHARGER CRADLE ASSEMBLY. Refer to  REMOVAL [11/2021 - 03/2024]  , or refer to  REMOVAL [03/2024 - ] 

    Result: 

    NG 

    See step  13

  13. CONFIRM VEHICLE SPECIFICATION 
    1. Choose the model to be inspected.

      Result

      Result Proceed to
      w/o Headup Display A
      w/ Headup Display B

    Result: 

    B 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    A 

    See step  14

  14. CHECK FOR SHORT IN CAN BUS LINE (COMBINATION METER ASSEMBLY DISCONNECTED) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the D22 combination meter assembly connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.
      GTY1065082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Transmission Floor Shift Assembly (Shift Control ECU))

      Standard Resistance

      Tester Connection Condition Specified Condition
      D39-21 (CA3H) or D39-6 (CA3L) - Body ground Cable from negative (-) auxiliary battery terminal disconnected 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. Reconnect the combination meter assembly connector.
    5. Connect the cable to the negative (-) auxiliary battery terminal.

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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