CAN COMMUNICATION SYSTEM, Diagnostic DTC:U1002, U0233

DTC Code DTC Name
U1002 Lost Communication with Gateway Module (Network Gateway ECU)
U0233 Lost Communication with Blind Spot Monitor Master Module

DESCRIPTION

DTC No. DTC Detection Condition Trouble Area
U0233 No communication from the blind spot monitor sensor RH continues.

  • Blind spot monitor sensor RH branch line or connector

  • Power source circuit of blind spot monitor sensor RH

  • Blind spot monitor sensor RH ground circuit

  • Blind spot monitor sensor RH
U1002 Network gateway ECU cannot receive signals from all ECUs that have been memorized as those connected to sub bus 2.

  • Open or short in sub bus 2 main line or connector

  • Open or short in sub bus 2 branch line or connector

  • Network gateway ECU

  • Blind spot monitor sensor RH

  • Power source circuit of blind spot monitor sensor RH

  • Blind spot monitor sensor RH ground circuit

  • Open or short in CAN No. 3 junction connector

  • Open or short in CAN No. 5 junction connector

Tech Tips

This diagnosis procedure is for when DTC U1002 is output by the network gateway ECU (Techstream display: Gateway).

WIRING DIAGRAM

A011SARE01

INSPECTION PROCEDURE

Note

  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key, switches or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work Click here.

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output Click here.

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

  • DTC check procedure: Turn the ignition switch to ON, turn the blind spot monitor system on using the blind spot monitor main switch (ON/OFF switch), wait at least 22 seconds and then drive the vehicle at a speed of 5 km/h (3 mph) or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed Click here.

Tech Tips

  • Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE

  1. CHECK SUB BUS 2

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

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

      A011SX3E10
      Standard Resistance
      Tester Connection Condition Specified Condition Result
      I81-13 (CA2H) - I81-12 (CA2L) Cable disconnected from negative (-) battery terminal 54 to 69 Ω

      Below 54 Ω:

      Short circuit between bus lines

      70 Ω or higher:

      Open circuit in a main bus line
      I81-13 (CA2H) - I81-4 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANH ground short
      I81-12 (CA2L) - I81-4 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANL ground short
      I81-13 (CA2H) - I81-2 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANH +B short
      I81-12 (CA2L) - I81-2 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANL +B short
      Text in Illustration
      *a

      Component with harness connector

      (Network Gateway ECU)
      Result
      Result Proceed to
      OK A
      Open circuit in CAN main bus line B
      Short circuit between bus lines C

      • Ground short

      • +B short

      		 D
    B

    CHECK FOR OPEN IN SUB BUS 2 LINES (NETWORK GATEWAY ECU) Click here

    C

    CHECK FOR SHORT IN SUB BUS 2 LINES (NETWORK GATEWAY ECU) Click here

    D

    CHECK FOR SHORT IN SUB BUS 2 LINE (CAN NO. 3 J/C) Click here

    A

  2. CHECK FOR OPEN IN SUB BUS 2 BRANCH LINES (BLIND SPOT MONITOR SENSOR RH)

    1. Disconnect the connector from the blind spot monitor sensor RH.

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

      A011SMTE22
      Standard Resistance
      Tester Connection Condition Specified Condition
      O28-2 (CA1P) - O28-7 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Blind Spot Monitor Sensor RH)
    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (BLIND SPOT MONITOR SENSOR RH - CAN NO. 3 J/C)

    OK

  3. CHECK FOR POWER SOURCE CIRCUIT (BLIND SPOT MONITOR SENSOR RH)

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

      A011SMTE23
      Standard Resistance
      Tester Connection Condition Specified Condition
      O28-10 (BRGD) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Blind Spot Monitor Sensor RH)

    2. Reconnect the cable to the negative (-) battery terminal.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      O28-5 (BRB) - Body ground Ignition switch ON 11 to 14 V
    NG

    REPAIR OR REPLACE POWER SOURCE CIRCUIT (BLIND SPOT MONITOR SENSOR RH)

    OK

  4. CHECK FOR DTC OUTPUT

    1. Reconnect the connector to the blind spot monitor sensor RH.

    2. Connect the Techstream to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the Techstream on.

    5. Clear the DTCs.

    6. Turn the ignition switch off.

    7. Turn the ignition switch to ON.

    8. Turn the Techstream on.

    9. Check for DTCs.

      Result
      Result Proceed to
      U1002 is not output A
      U1002 is output B
    B

    REPLACE NETWORK GATEWAY ECU Click here

    A

    SYMPTOM SIMULATION Click here

  5. REPLACE NETWORK GATEWAY ECU

    1. Replace the network gateway ECU Click here.

    NEXT

  6. CHECK FOR DTC OUTPUT

    1. Connect the Techstream to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the Techstream on.

    4. Recheck for DTCs.

      Result
      Result Proceed to
      U1002 is not output A
      U1002 is output B
    B

    REPLACE BLIND SPOT MONITOR SENSOR RH Click here

    A

    END

  7. CHECK FOR OPEN IN SUB BUS 2 LINES (NETWORK GATEWAY ECU)

    1. Disconnect the network gateway ECU connector.

      A011UZ4E28

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I81-13 (CA2H) - I81-12 (CA2L) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Network Gateway ECU)
    NG

    CHECK FOR OPEN IN SUB BUS 2 LINES (CAN NO. 3 J/C) Click here

    OK

    REPLACE NETWORK GATEWAY ECU Click here

  8. CHECK FOR OPEN IN SUB BUS 2 LINES (CAN NO. 3 J/C)

    1. Reconnect the network gateway ECU connector.

    2. Disconnect the wire harness connector from the CAN No. 3 junction connector.

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

      A011UE5E22
      Standard Resistance
      Tester Connection Condition Specified Condition
      O30-10 (CANH) - O30-21 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      O30-11 (CANH) - O30-22 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)
      *b to CAN No. 5 Junction Connector
      *c to Network Gateway ECU
      Result
      Result Proceed to
      OK A
      NG (to Network gateway ECU main bus line) B
      NG (to CAN No. 5 junction connector main bus line) C
    B

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - NETWORK GATEWAY ECU)

    C

    CHECK FOR OPEN IN SUB BUS 2 LINES (CAN NO. 5 J/C) Click here

    A

    REPLACE CAN NO. 3 JUNCTION CONNECTOR

  9. CHECK FOR OPEN IN SUB BUS 2 LINES (CAN NO. 5 J/C)

    1. Reconnect the wire harness connector to the CAN No. 3 junction connector.

    2. Disconnect the instrument panel wire from the CAN No. 5 junction connector.

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

      A011QRYE23
      Standard Resistance
      Tester Connection Condition Specified Condition
      T16-3 (CANH) - T16-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to CAN No. 5 Junction Connector)
      *b to CAN No. 3 Junction Connector
    NG

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - CAN NO. 5 J/C)

    OK

    REPLACE CAN NO. 5 JUNCTION CONNECTOR

  10. CHECK FOR SHORT IN SUB BUS 2 LINES (NETWORK GATEWAY ECU)

    1. Disconnect the network gateway ECU connector.

      A011UZ4E28

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I81-13 (CA2H) - I81-12 (CA2L) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Network Gateway ECU)
    NG

    CHECK FOR SHORT IN SUB BUS 2 LINES (CAN NO. 3 J/C) Click here

    OK

    REPLACE NETWORK GATEWAY ECU Click here

  11. CHECK FOR SHORT IN SUB BUS 2 LINES (CAN NO. 3 J/C)

    1. Reconnect the network gateway ECU connector.

    2. Disconnect the wire harness connector from the CAN No. 3 junction connector.

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

      A011UE5E20
      Standard Resistance
      Tester Connection Condition Specified Condition
      O30-9 (CANH) - O30-20 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      O30-10 (CANH) - O30-21 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      O30-11 (CANH) - O30-22 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)
      *b to Blind Spot Monitor Sensor RH
      *c to CAN No. 5 Junction Connector
      *d to Network Gateway ECU
      Result
      Result Proceed to
      OK A
      NG (to Network gateway ECU main bus line) B
      NG (to CAN No. 5 junction connector main bus line) C
      NG (to Blind spot monitor sensor RH) D
    B

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - NETWORK GATEWAY ECU)

    C

    CHECK FOR SHORT IN SUB BUS 2 LINES (CAN NO. 5 J/C) Click here

    D

    CHECK FOR SHORT IN SUB BUS 2 LINES (ECUS) Click here

    A

    REPLACE CAN NO. 3 JUNCTION CONNECTOR

  12. CHECK FOR SHORT IN SUB BUS 2 LINES (CAN NO. 5 J/C)

    1. Reconnect the wire harness connector to the CAN No. 3 junction connector.

    2. Disconnect the wire harness connector from the CAN No. 5 junction connector.

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

      A011QRYE23
      Standard Resistance
      Tester Connection Condition Specified Condition
      T16-3 (CANH) - T16-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to CAN No. 5 Junction Connector)
      *b to CAN No. 3 Junction Connector
    NG

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - CAN NO. 5 J/C)

    OK

    REPLACE CAN NO. 5 JUNCTION CONNECTOR

  13. CHECK FOR SHORT IN SUB BUS 2 LINES (ECUS)

    1. Reconnect all wire harness connectors (CAN No. 3 junction connector).

    2. Disconnect the connector that includes terminals CANH and CANL from the ECU (or sensor) to which the short-circuited branch line is connected Click here.

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

      A011SX3E11
      Standard Resistance
      Tester Connection Condition Specified Condition
      I81-13 (CA2H) - I81-12 (CA2L) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Text in Illustration
      *a

      Component with harness connector

      (Network Gateway ECU)

      Tech Tips

      • If the resistance becomes normal (between 54 and 69 Ω) when the connector is disconnected from the ECU (or sensor), there may be a short in the ECU (or sensor).

      • If the resistance does not become normal (between 54 and 69 Ω) when the connector is disconnected from the ECU (or sensor), repair or replace the short-circuited branch line or connector.

    NG

    REPAIR OR REPLACE CORRESPONDING ECU WIRE

    OK

    REPLACE CORRESPONDING ECU

  14. CHECK FOR SHORT IN SUB BUS 2 LINE (CAN NO. 3 J/C)

    1. Disconnect the wire harness connector from the CAN No. 3 junction connector.

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

      A011QQJE07
      Standard Resistance
      Tester Connection Condition Specified Condition Purpose Connected to
      O30-9 (CANH) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Inspection for CANH ground short Blind spot monitor sensor RH
      O30-20 (CANL) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Inspection for CANL ground short
      O30-10 (CANH) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Inspection for CANH ground short CAN No. 5 junction connector
      O30-21 (CANL) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Inspection for CANL ground short
      O30-11 (CANH) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Inspection for CANH ground short Network gateway ECU
      O30-22 (CANL) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Inspection for CANL ground short
      O30-9 (CANH) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANH +B short Blind spot monitor sensor RH
      O30-20 (CANL) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANL +B short
      O30-10 (CANH) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANH +B short CAN No. 5 junction connector
      O30-21 (CANL) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANL +B short
      O30-11 (CANH) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANH +B short Network gateway ECU
      O30-22 (CANL) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANL +B short
      Text in Illustration
      *1 DLC3 - -
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)

      		 *b to Blind Spot Monitor Sensor RH
      *c to CAN No. 5 Junction Connector *d to Network Gateway ECU
      Result
      Result Proceed to
      OK A
      NG (to Network gateway ECU main bus line) B
      NG (to CAN No. 5 junction connector main bus line) C
      NG (to Blind spot monitor sensor RH) D

      Tech Tips

      It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 2 inspection.

      Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 2 inspection.

    B

    CHECK FOR SHORT IN SUB BUS 2 LINE (NETWORK GATEWAY ECU) Click here

    C

    CHECK FOR SHORT IN SUB BUS 2 LINE (CAN NO. 5 J/C) Click here

    D

    CHECK SUB BUS 2 LINE (ECUS) Click here

    A

    REPLACE CAN NO. 3 JUNCTION CONNECTOR

  15. CHECK FOR SHORT IN SUB BUS 2 LINE (NETWORK GATEWAY ECU)

    1. Disconnect the network gateway ECU connector.

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

      A011UZ4E29
      Standard Resistance
      Tester Connection Condition Specified Condition Purpose
      I81-13 (CA2H) - I81-4 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANH ground short
      I81-12 (CA2L) - I81-4 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANL ground short
      I81-13 (CA2H) - I81-2 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANH +B short
      I81-12 (CA2L) - I81-2 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANL +B short
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Network Gateway ECU)

      Tech Tips

      It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 2 inspection.

      Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 2 inspection.

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - NETWORK GATEWAY ECU)

    OK

    REPLACE NETWORK GATEWAY ECU Click here

  16. CHECK FOR SHORT IN SUB BUS 2 LINE (CAN NO. 5 J/C)

    1. Disconnect the wire harness connector from the CAN No. 5 junction connector.

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

      A011SZIE08
      Standard Resistance
      Tester Connection Condition Specified Condition Purpose
      T16-3 (CANH) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANH ground short
      T16-2 (CANL) - I39-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANL ground short
      T16-3 (CANH) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANH +B short
      T16-2 (CANL) - I39-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANL +B short
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to CAN No. 5 Junction Connector)

      Tech Tips

      It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 2 inspection.

      Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 2 inspection.

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - CAN NO. 5 J/C)

    OK

    REPLACE CAN NO. 5 JUNCTION CONNECTOR

  17. CHECK SUB BUS 2 LINE (ECUS)

    1. Reconnect all wire harness connector (CAN No. 3 junction connector).

    2. Disconnect the connector that includes terminals CANH and CANL from the ECU to which the bus line shorted to B+ or shorted to GND is connected.

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

      A011SX3E10
      Standard Resistance
      Tester Connection Condition Specified Condition Purpose
      I81-13 (CA2H) - I81-4 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANH ground short
      I81-12 (CA2L) - I81-4 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Below 200 Ω:

      CANL ground short
      I81-13 (CA2H) - I81-2 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANH +B short
      I81-12 (CA2L) - I81-2 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Below 6 kΩ:

      CANL +B short
      Text in Illustration
      *a

      Component with harness connector

      (Network Gateway ECU)

      Tech Tips

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 2 inspection.

      • If the resistance becomes abnormal when an ECU connector is reconnected, there may be a short in the ECU.

        Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 2 inspection.

    NG

    REPAIR OR REPLACE CORRESPONDING ECU WIRE

    OK

    REPLACE CORRESPONDING ECU