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Home >> Lexus >> 2017 >> RX 450h Base >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> Hybrid Control System (Diagnostic Codes (10 Of 10) & Circuit Tests) >> Hybrid Control System >> DTC U0110-159: Lost Communication with Drive Motor Control Module "A"; DTC U0110-656: Lost Communication with Drive Motor Control Module "A"; DTC U0110-657: Lost Communication with Drive Motor Control Module "A" [10/2015 - ] >> Procedure
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DTC U0110-159: Lost Communication with Drive Motor Control Module "A"; DTC U0110-656: Lost Communication with Drive Motor Control Module "A"; DTC U0110-657: Lost Communication with Drive Motor Control Module "A" [10/2015 - ]: Procedure

  1. INSPECT FUSE (PCU) 
    1. Remove the PCU fuse from the No. 2 engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.
      GTY676185Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 No. 2 Engine Room Relay Block
      *2 PCU Fuse

      Standard Resistance

      Tester Connection Condition Specified Condition
      PCU fuse terminals Always Below 1 Ω
    3. Install the PCU fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  2

  2. CLEAR DTC 

    Refer to PROCEDURE - Step 4

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK DTC OUTPUT (HYBRID CONTROL) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
    4. Check for DTCs.

      Powertrain > Hybrid Control > Trouble Codes 

      Result

      Proceed to
      U0110-159, 656 or 657 is output.
      U0110-159, 656 and 657 are not output.
    5. Turn the power switch off.

    Result: 

    U0110-159, 656 and 657 are not output. 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [10/2015 - ] 

    Result: 

    U0110-159, 656 or 657 is output. 

    See step  4

  4. CHECK INVERTER WITH CONVERTER ASSEMBLY (GENERATOR CABLE CONNECTION CONDITION) 

    See step  1

    Result

    Result Proceed to
    The terminals are connected securely and there are no contact problems. There are no arc marks. A
    The terminals are not connected securely and there is a contact problem. There are arc marks. B
    The terminals are not connected securely and there is a contact problem. There are no arc marks. C
    The terminals are connected securely and there are no contact problems. There are arc marks. B

    Result: 

    B 

    REPLACE MALFUNCTIONING PARTS 

    Result: 

    C 

    CONNECT SECURELY 

    Result: 

    A 

    See step  5

  5. CHECK INVERTER WITH CONVERTER ASSEMBLY (MOTOR CABLE CONNECTION CONDITION) 

    See step  1

    Result

    Result Proceed to
    The terminals are connected securely and there are no contact problems. There are no arc marks. A
    The terminals are not connected securely and there is a contact problem. There are arc marks. B
    The terminals are not connected securely and there is a contact problem. There are no arc marks. C
    The terminals are connected securely and there are no contact problems. There are arc marks. B

    Result: 

    B 

    REPLACE MALFUNCTIONING PARTS 

    Result: 

    C 

    CONNECT SECURELY 

    Result: 

    A 

    See step  6

  6. CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (GENERATOR (MG1)) 

    See step  2

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 12/2017]  , or refer to  REMOVAL [12/2017 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  7

  7. CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MOTOR (MG2)) 

    See step  2

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 12/2017]  , or refer to  REMOVAL [12/2017 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY POWER SOURCE CIRCUIT) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the service information because this may cause a malfunction.

    2. Disconnect the A38 inverter with converter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY644462Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)

      Standard Resistance

      Tester Connection Condition Specified Condition
      A38-10 (GND1) - Body ground Power switch off Below 1 Ω
      A38-11 (GND2) - Body ground Power switch off Below 1 Ω
    4. Connect the cable to the negative (-) auxiliary battery terminal.
    5. Turn the power switch on (IG).
    6. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A38-30 (+B) - Body ground Power switch on (IG) 11 to 14 V
      A38-31 (+B2) - Body ground Power switch on (IG) 11 to 14 V
      NOTE:

      Turning the power switch on (IG) with the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.
    8. Disconnect the cable from the negative (-) auxiliary battery terminal.
    9. Reconnect the A38 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (CHECK WAVEFORM) 
    1. Connect an oscilloscope between the hybrid vehicle control ECU assembly terminals specified in the following table.
    2. Turn the power switch on (IG).
    3. Measure the waveform.
      GTY627621Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Hybrid Vehicle Control ECU Assembly)
      Item Contents
      Tester Connection CH1: A40-33 (CLK+) - J2-6 (E1)
      CH2: A40-32 (CLK-) - J2-6 (E1)
      Equipment Setting 1 V/DIV., 1 μs./DIV.
      Condition Power switch on (IG)

      Result

      Proceed to
      The waveform appears as shown in the illustration.
      The waveform differs from the one shown in the illustration.

      HINT: 

      • Inspect with the connector connected.
      • If pulses are generated, the shape of the waveform can be assumed to be normal.
      • The shape of the waveform may vary according to communication conditions.
    4. Turn the power switch off.

    Result: 

    The waveform differs from the one shown in the illustration. 

    See step  13

    Result: 

    The waveform appears as shown in the illustration. 

    See step  10

  10. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (CHECK WAVEFORM) 
    1. Connect an oscilloscope between the hybrid vehicle control ECU assembly terminals specified in the following table.
    2. Turn the power switch on (IG).
    3. Measure the waveform.
      GTY644021Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Hybrid Vehicle Control ECU Assembly)
      Item Contents
      Tester Connection CH1: A40-31 (REQ+) - J2-6 (E1)
      CH2: A40-30 (REQ-) - J2-6 (E1)
      Equipment Setting 1 V/DIV., 1 ms./DIV.
      Condition Power switch on (IG)

      Result

      Proceed to
      The waveform appears as shown in the illustration.
      The waveform differs from the one shown in the illustration.

      HINT: 

      • Inspect with the connector connected.
      • If pulses are generated, the shape of the waveform can be assumed to be normal.
      • The shape of the waveform may vary according to communication conditions.
    4. Turn the power switch off.

    Result: 

    The waveform differs from the one shown in the illustration. 

    See step  15

    Result: 

    The waveform appears as shown in the illustration. 

    See step  11

  11. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (CHECK WAVEFORM) 
    1. Connect an oscilloscope between the hybrid vehicle control ECU assembly terminals specified in the following table.
    2. Turn the power switch on (IG).
    3. Measure the waveform.
      GTY677624Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Hybrid Vehicle Control ECU Assembly)
      Item Contents
      Tester Connection CH1: A40-23 (MTH+) - J2-6 (E1)
      CH2: A40-22 (MTH-) - J2-6 (E1)
      Equipment Setting 1 V/DIV., 200 μs./DIV.
      Condition Power switch on (IG)

      Result

      Proceed to
      The waveform appears as shown in the illustration.
      The waveform differs from the one shown in the illustration.

      HINT: 

      • Inspect with the connector connected.
      • If pulses are generated, the shape of the waveform can be assumed to be normal.
      • The shape of the waveform may vary according to communication conditions.
    4. Turn the power switch off.

    Result: 

    The waveform appears as shown in the illustration. 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    The waveform differs from the one shown in the illustration. 

    See step  17

  12. REPLACE FUSE (PCU) 
    1. Replace the PCU fuse.
      GTY676185Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 No. 2 Engine Room Relay Block
      *2 PCU Fuse
    2. Turn the power switch on (READY).
    3. Check if there is an open circuit in the PCU fuse in the No. 2 engine room relay block.

      OK

      There is no open circuit in the PCU fuse.

      HINT: 

      If the fuse does not become open again after turning the power switch on (READY), it can be assumed that the previous fuse failed due to age.

    4. Turn the power switch off.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    COMPLETED 

    Result: 

    NG 

    See step  19

  13. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - INVERTER WITH CONVERTER ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the service information because this may cause a malfunction.

    2. Disconnect the A40 hybrid vehicle control ECU assembly connector.
    3. Disconnect the A38 inverter with converter assembly connector.
    4. Connect the cable to the negative (-) auxiliary battery terminal.
    5. Turn the power switch on (IG).
    6. Measure the voltage according to the value(s) in the table below.
      GTY650841Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)
      *b Front view of wire harness connector
      (to Inverter with Converter Assembly)

      Standard Voltage

      Tester Connection Condition Specified Condition
      A40-33 (CLK+) - Body ground Power switch on (IG) Below 1 V
      A40-32 (CLK-) - Body ground Power switch on (IG) Below 1 V
      NOTE:

      Turning the power switch on (IG) with the hybrid vehicle control ECU assembly connector and the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.
    8. Disconnect the cable from the negative (-) auxiliary battery terminal.
    9. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A40-33 (CLK+) - A38-7 (CLK+) Power switch off Below 1 Ω
      A40-32 (CLK-) - A38-18 (CLK-) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A40-33 (CLK+) or A38-7 (CLK+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A40-32 (CLK-) or A38-18 (CLK-) - Body ground and other terminals Power switch off 10 kΩ or higher
    10. Reconnect the A38 inverter with converter assembly connector.
    11. Reconnect the A40 hybrid vehicle control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. CHECK INVERTER WITH CONVERTER ASSEMBLY 
    1. Disconnect the A40 hybrid vehicle control ECU assembly connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY673763Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)

      Standard Resistance

      Tester Connection Condition Specified Condition
      A40-33 (CLK+) - A40-32 (CLK-) Power switch off 80 to 170 Ω
    3. Reconnect the A40 hybrid vehicle control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 12/2017]  , or refer to  REMOVAL [12/2017 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

  15. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - INVERTER WITH CONVERTER ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the service information because this may cause a malfunction.

    2. Disconnect the A40 hybrid vehicle control ECU assembly connector.
    3. Disconnect the A38 inverter with converter assembly connector.
    4. Connect the cable to the negative (-) auxiliary battery terminal.
    5. Turn the power switch on (IG).
    6. Measure the voltage according to the value(s) in the table below.
      GTY650842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)
      *b Front view of wire harness connector
      (to Inverter with Converter Assembly)

      Standard Voltage

      Tester Connection Condition Specified Condition
      A40-31 (REQ+) - Body ground Power switch on (IG) Below 1 V
      A40-30(REQ-) - Body ground Power switch on (IG) Below 1 V
      NOTE:

      Turning the power switch on (IG) with the hybrid vehicle control ECU assembly connector and the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.
    8. Disconnect the cable from the negative (-) auxiliary battery terminal.
    9. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A40-31 (REQ+) - A38-26 (REQ+) Power switch off Below 1 Ω
      A40-30(REQ-) - A38-37 (REQ-) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A40-31 (REQ+) or A38-26 (REQ+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A40-30(REQ-) or A38-37 (REQ-) - Body ground and other terminals Power switch off 10 kΩ or higher
    10. Reconnect the A38 inverter with converter assembly connector.
    11. Reconnect the A40 hybrid vehicle control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  16

  16. CHECK INVERTER WITH CONVERTER ASSEMBLY 
    1. Disconnect the A40 hybrid vehicle control ECU assembly connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY673764Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)

      Standard Resistance

      Tester Connection Condition Specified Condition
      A40-31 (REQ+) - A40-30 (REQ-) Power switch off 80 to 170 Ω
    3. Reconnect the A40 hybrid vehicle control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 12/2017]  , or refer to  REMOVAL [12/2017 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

  17. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - INVERTER WITH CONVERTER ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the service information because this may cause a malfunction.

    2. Disconnect the A40 hybrid vehicle control ECU assembly connector.
    3. Disconnect the A38 inverter with converter assembly connector.
    4. Connect the cable to the negative (-) auxiliary battery terminal.
    5. Turn the power switch on (IG).
    6. Measure the voltage according to the value(s) in the table below.
      GTY650839Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)
      *b Front view of wire harness connector
      (to Inverter with Converter Assembly)

      Standard Voltage

      Tester Connection Condition Specified Condition
      A40-23 (MTH+) - Body ground Power switch on (IG) Below 1 V
      A40-22 (MTH-) - Body ground Power switch on (IG) Below 1 V
      NOTE:

      Turning the power switch on (IG) with the hybrid vehicle control ECU assembly connector and the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.
    8. Disconnect the cable from the negative (-) auxiliary battery terminal.
    9. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A40-23 (MTH+) - A38-8 (MTH+) Power switch off Below 1 Ω
      A40-22 (MTH-) - A38-19 (MTH-) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A40-23 (MTH+) or A38-8 (MTH+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A40-22 (MTH-) or A38-19 (MTH-) - Body ground and other terminals Power switch off 10 kΩ or higher
    10. Reconnect the A38 inverter with converter assembly connector.
    11. Reconnect the A40 hybrid vehicle control ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  18

  18. CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the service information because this may cause a malfunction.

    2. Disconnect the A38 inverter with converter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY621870Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Hybrid Vehicle Control ECU)

      Standard Resistance

      Tester Connection Condition Specified Condition
      A40-23 (MTH+) -A40-22 (MTH-) Power switch off 80 to 170 Ω
    4. Reconnect the A38 inverter with converter assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 12/2017]  , or refer to  REMOVAL [12/2017 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

  19. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - NO. 2 ENGINE ROOM RELAY BLOCK) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the service information because this may cause a malfunction.

    2. Remove the PCU fuse from the No. 2 engine room relay block.
    3. Disconnect the A38 inverter with converter assembly connector.
    4. Measure the resistance according to the value(s) in the table below.
      GTY677431Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 No. 2 Engine Room Relay Block *2 PCU Fuse
      *a Front view of wire harness connector
      (to Inverter with Converter Assembly)      		 - -

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A38-30 (+B), A38-31 (+B2) or 2 (PCU fuse terminal) - Body ground and other terminals Power switch off 10 kΩ or higher
    5. Reconnect the A38 inverter with converter assembly connector.
    6. Install the PCU fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  21

    Result: 

    OK 

    See step  20

  20. REPLACE INVERTER WITH CONVERTER ASSEMBLY 

    Refer to REMOVAL [10/2015 - 08/2016] , or refer to REMOVAL [08/2016 - 12/2017] , or refer to REMOVAL [12/2017 - 08/2019] , or refer to REMOVAL [08/2019 - ]

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    REPLACE FUSE (PCU) 

  21. REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    REPLACE FUSE (PCU) 

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