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How To Proceed With Troubleshooting [09/2014 - 10/2015]: Procedure

  1. VEHICLE BROUGHT TO WORKSHOP 

    HINT: 

    • If the engine switch can be turned to on (IG) when the vehicle is brought in for repair, check for DTCs and check the illumination condition of the indicators in the combination meter assembly and the basic operation of the vehicle (such as steering operation) promptly.
    • Do not turn the engine switch off until the inspection of the vehicle is finished, as some fail-safe functions are canceled when the engine switch is turned off.
    • If the engine switch cannot be turned to on (IG) when the vehicle is brought in, measure the voltage of the battery. If the voltage is below 11 V, recharge or replace the battery before performing troubleshooting.
    • If the engine switch cannot be turned to on (IG) even though the battery voltage is normal, repair this malfunction before performing troubleshooting (Refer to PROBLEM SYMPTOMS TABLE [09/2014 - ] ).

    Result

    Result
    NEXT

    Result: 

    NEXT 

    See step  2

  2. CUSTOMER PROBLEM ANALYSIS 

    HINT: 

    • When troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
    • Ask the customer if the vehicle is/was equipped with additional devices such as a theft deterrent device or monitor. (If equipped, explain the customer that the additional devices will be removed before performing troubleshooting as the malfunction cannot be checked properly.)
    1. It is useful to confirm the symptoms and the conditions in which the vehicle was operating at the time when a malfunction occurred. This helps to narrow down the malfunctioning part.

      HINT: 

      • What was affected (system, part or meter warning indicators)
      • What happened (details of the malfunction)
      • When (occurrence date and time, frequency and if it recurs or not)
      • Under what kind of situation did the problem occur (driving and operating condition at the occurrence and weather)
      • Road type or condition (city, suburb, paved road, unpaved road, highway, etc.)
      • Return conditions (what made the vehicle return to normal. Example: engine switch was turned off)
      POINTS TO BE CONFIRMED

      Symptom
      • Air conditioning
        • Was the air conditioner operating
        • Were you able to operate the air conditioner using the remote starter
      • Electronic power steering system
        • Was the power steering operating
        • How was the electronic power steering force
        • Did the steering feel strange at all
      • Drive monitor display
        • Did the display update properly
        • Were numbers displayed for the estimated distance to empty
      • Eco-navigation (eco-drive) display
        • Was the graph that displays fuel consumption per minute being updated
        • Was the graph that displays fuel consumption in intervals displaying the most recent value
        • Was the estimated distance to empty displayed on the screen that displays the graph for fuel consumption in intervals
      • Interior foot illumination
        • When opening and closing the door, does the foot illumination turn on and off accordingly
        • When the engine switch is turned on (IG), does the foot illumination turn off
      • Lock and unlock operation
        • Do the doors lock when the vehicle is being driven
        • Do the shift-linked automatic door lock and unlock functions operate
      • Smart access system
        • Do the entry lock and unlock functions operate
        • Does the smart warning system operate
        • Do the lights turn on
      • Tilt and telescopic
        • Do the memory, recall, auto-return and autoaway functions operate
      • Seat
        • Do the memory recall and return/away functions operate
      • Was there any other system behavior that you noticed
      Combination meter assembly warning lights
      • State of the warning lights and the order in which they illuminate
        • Brake warning light / yellow (minor malfunction) or red (malfunction)
        • ABS warning light
        • SRS warning light
        • EPS warning light
        • VGRS warning light
        • SLIP warning light
        • AFS OFF indicator blinks
        • PCS indicator blinks
        • CRUISE indicator blinks
        • Other lights
      • Gauges/indicators in the combination meter
        • Speedometer
        • Tachometer
        • Fuel gauge
        • Shift indicator
        • Other gauges or indicators

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK TECHSTREAM OPERATION 

    HINT: 

    Read the Techstream operator's manual before use (Refer to GENERAL INFORMATION [09/2014 - ] ).

    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check that the Techstream and ECUs can communicate with the engine switch on (IG).

      HINT: 

      • If communication is impossible, the Techstream screen will indicate an error.
      • If communication between the Techstream and ECUs is impossible, either the Techstream or vehicle has a malfunction.
      • When communication between the Techstream and the vehicle is impossible, but communication is possible when the Techstream is connected to another vehicle, the vehicle has the malfunction. Inspect the CANH and CANL branch lines of the DLC3 and the ECU power source circuits (in this case perform steps 7 to 9 first). In addition, check that the BAT terminal of the DLC3 receives battery voltage (11 V or more).
      • If communication between the Techstream and ECUs is still impossible even when the Techstream is connected to another vehicle, the Techstream has a malfunction. Perform the self tests described in the Techstream operator's manual. (The Techstream may be malfunctioning or its battery may be discharged.)

      Result

      Result Proceed to
      OK (Communication between the Techstream and the vehicle is possible.) A
      OK (Communication between the Techstream and the vehicle is impossible but communication is possible when connected to another vehicle.) B
      NG (Communication is not possible between the Techstream and the vehicle, nor between the Techstream and another vehicle.) C

    Result: 

    See step  7

    Result: 

    Refer to Techstream operator's manual 

    Result: 

    See step  4

  4. CHECK DTC 
    1. Using the Techstream, perform Health Check to read current and history DTCs and record them.
      NOTE:
      • CAN communication DTCs are output when there is an open or short in any of the communication lines. Any problems with the power source of a corresponding ECU or sensor, or problems in the ECU, the sensor itself also cause these DTCs to be output.
      • If a CAN communication line connector is disconnected with the engine switch on (IG), the ECUs of the corresponding system and related systems store a DTC.

      HINT: 

      • If an open in a CAN main bus line, a short between the CAN bus lines (CANH and CANL) or a +B or ground short in a CAN bus occurs, DTCs of almost all ECUs and sensors on the CAN bus may be output (or a message indicating a communication error may be displayed on the Techstream screen). In this case, check the resistance of the CAN bus (steps 7 to 9) first.
      • If an open occurs in just one of the lines of a CAN branch, DTCs which are not related to malfunctioning parts may be output (DTCs may be displayed randomly), or a message indicating a communication error may be displayed on the Techstream.
    2. Read the freeze frame data using the Techstream and record it.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. PERFORM COMMUNICATION MALFUNCTION CHECK (CONNECTION STATUS CHECK USING TECHSTREAM) 
    1. Select "Communication Malfunction Check" from the screen on the Techstream.
    2. Record all the DTCs stored for ECUs and sensors.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  6

  6. CHECK CAN BUS CHECK (CONNECTION STATUS CHECK USING TECHSTREAM) 
    1. Based on the vehicle equipment and specifications, confirm the systems that use CAN communication (Refer to DIAGNOSIS SYSTEM [09/2014 - 10/2015] ).
    2. Select "CAN Bus Check" from the screen on the Techstream.
    3. Observe the screen for approximately 2 minutes to check the ECUs and sensors displayed on the screen.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  7. CHECK DLC3 BRANCH LINE AND V BUS MAIN LINE (CANH - CANL) 
    NOTE:

    Before measuring the resistance of the CAN bus, turn the engine 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.

    HINT: 

    Operating the engine 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.

    1. Disconnect the cable from the negative (-) battery terminal.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N20-6 (CANH) - N20-14 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      GTY530982Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of DLC3

      Result

      Result Proceed to
      OK A
      NG (70 Ω or higher) B
      NG (Below 53 Ω) C

    Result: 

    GO TO "Open in CAN Main Wire" 

    (Refer to Open in CAN Main Wire [09/2014 - 10/2015] )

    Result: 

    GO TO "Short in CAN Bus Lines" 

    (Refer to Short in CAN Bus Lines [09/2014 - 10/2015] )

    Result: 

    See step  8

  8. CHECK FOR SHORT TO GND IN V BUS (CANH, CANL - CG) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N20-6 (CANH) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N20-14 (CANL) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      GTY530873Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of DLC3

      Result

      Result Proceed to
      OK A
      NG B

    Result: 

    GO TO "Short to GND in CAN Bus Line" 

    (Refer to Short to GND in CAN Bus Line [09/2014 - 10/2015] )

    Result: 

    See step  9

  9. CHECK FOR SHORT TO +B IN V BUS (CANH, CANL - BAT) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N20-6 (CANH) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      N20-14 (CANL) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      GTY535587Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of DLC3

      Result

      Result Proceed to
      OK A
      NG B

    Result: 

    GO TO "Short to B+ in CAN Bus Line" 

    (Refer to Short to B+ in CAN Bus Line [09/2014 - 10/2015] )

    Result: 

    See step  10

  10. CHECK RESULT OF CAN BUS CHECK (CONNECTION STATUS CHECK USING TECHSTREAM) 
    1. Inspect or repair the probable malfunctioning part based on the check result of step 6 (the step in which CAN Bus Check was performed).

      Result of CAN Bus Check (Connection Status Check Using Techstream)

      Result Proceed to
      All ECUs and sensors connected to CAN communication are displayed (CAN bus circuit currently normal) A
      • w/o Dynamic Rear Steering System:
        • When sub bus 2 is selected from the bus selection screen, none of the connected ECUs (sensors) are detected
        • DTC U1002 (network communication malfunction) is output by the network gateway ECU (the sub bus 2 main line has an open or short circuit)
      • w/ Dynamic Rear Steering System:
        • When sub bus 18 is selected from the bus selection screen, none of the connected ECUs (sensors) are detected
        • DTC U1002 (network communication malfunction) is output by the network gateway ECU (the sub bus 18 main line has an open or short circuit)
      B
      • When sub bus 19 is selected from the bus selection screen, none of the connected ECUs (sensors) are detected
      • DTC U1002 (network communication malfunction) is output by the network gateway ECU (the sub bus 19 main line has an open or short circuit)
      C
      • When sub bus 1 is selected from the bus selection screen, none of the connected ECUs (sensors) are detected
      • DTC U1002 (network communication malfunction) is output by the main body ECU (multiplex network body ECU) (the sub bus 1 main line has an open or short circuit)
      D
      • When sub bus 13 is selected from the bus selection screen, none of the connected ECUs (sensors) are detected
      • DTC U1002 (network communication malfunction) is output by the driving support ECU assembly (the sub bus 13 main line has an open or short circuit)
      E
      • When sub bus 15 is selected from the bus selection screen, none of the connected ECUs (sensors) are detected
      • DTC U1103 (network communication malfunction) is output by the certification ECU (smart key ECU assembly) (the sub bus 15 main line has an open or short circuit)
      F
      • w/o Dynamic Rear Steering System:
        1. None of the ECUs (sensors) connected to the network gateway ECU, sub bus 2 are detected (network gateway ECU communication stop mode)
      • w/ Dynamic Rear Steering System:
        1. None of the ECUs (sensors) connected to the network gateway ECU, sub bus 18 and sub bus 19 are detected (network gateway ECU communication stop mode)
      G
      An ECU (sensor) that is supposed to be connected to the CAN communication system (V bus) is not detected and does not appear on the screen (the branch line of the ECU (sensor) has an open circuit or there is a loss of communication) H
      • w/o Dynamic Rear Steering System:
        1. An ECU (sensor) that is supposed to be connected to the CAN communication system (sub bus 2) is not detected and does not appear on the screen (the branch line of the ECU (sensor) connected to sub bus 2 has an open circuit or there is a loss of communication)
          NOTE:

          DTCs indicating a communication malfunction (DTCs that start with U) for the ECUs (sensors) connected to the CAN communication system (sub bus 2) are output by the network gateway ECU. Therefore, determine the location of the malfunction using those DTCs.

      • w/ Dynamic Rear Steering System:
        1. An ECU (sensor) that is supposed to be connected to the CAN communication system (sub bus 18 and sub bus 19) is not detected and does not appear on the screen (the branch line of the ECU (sensor) connected to sub bus 18 or sub bus 19 has an open circuit or there is a loss of communication)
          NOTE:

          DTCs indicating a communication malfunction (DTCs that start with U) for the ECUs (sensors) connected to the CAN communication system (sub bus 18 and sub bus 19) are output by the network gateway ECU. Therefore, determine the location of the malfunction using those DTCs.

      I
      An ECU (sensor) that is supposed to be connected to the CAN communication system (sub bus 1) is not detected and does not appear on the screen (the branch line of the ECU (sensor) connected to sub bus 1 has an open circuit or there is a loss of communication)
      NOTE:

      DTCs indicating a communication malfunction (DTCs that start with U) for the ECUs (sensors) connected to the CAN communication system (sub bus 1) are output by the main body ECU (multiplex network body ECU). Therefore, determine the location of the malfunction using those DTCs.

      I
      An ECU (sensor) that is supposed to be connected to the CAN communication system (sub bus 13) is not detected and does not appear on the screen (the branch line of the ECU (sensor) connected to sub bus 13 has an open circuit or there is a loss of communication)
      NOTE:

      DTCs indicating a communication malfunction (DTCs that start with U) for the ECUs (sensors) connected to the CAN communication system (sub bus 2 and sub bus 13) are output by the driving support ECU assembly. Therefore, determine the location of the malfunction using those DTCs.

      I
      An ECU (sensor) that is supposed to be connected to the CAN communication system (sub bus 15) is not detected and does not appear on the screen (the branch line of the ECU (sensor) connected to sub bus 15 has an open circuit or there is a loss of communication)
      NOTE:

      DTCs indicating a communication malfunction (DTCs that start with U) for the ECUs (sensors) connected to the CAN communication system (sub bus 15) are output by the certification ECU (smart key ECU assembly). Therefore, determine the location of the malfunction using those DTCs.

      I
      ECUs (sensors) that are supposed to be connected to the CAN communication system do not appear on the screen and other ECUs (sensors) appear and reappear on the screen during confirmation (one of the branch lines of the ECU (sensor) has an open circuit) J
      NOTE:
      • Non-installed ECUs or sensors will not be displayed. Do not mistake them for being in communication stop mode.
      • It may be possible to select buses that do not have ECUs or sensors from the bus selection pull-down menu on the Techstream. This is not a malfunction. (This occurs when optional devices are not on a sub bus that is monitored by a gateway function equipped ECU.)

      HINT: 

      • Regarding CAN Bus Check, refer to How to Interpret CAN Bus Diagnosis (CAN Bus Check) Screen (Refer to DIAGNOSIS SYSTEM [09/2014 - 10/2015] ).
      • If the display of an ECU is intermittent during the check, one side of an ECU or sensor CAN branch wire is open (the signal of the ECU is treated as noise, which affects the response and display of the Techstream).
      • The main body ECU (multiplex network body ECU) checks for proper ECU communication for ECUs that are connected to the sub bus 1 and the results are displayed on the Techstream. ECUs that stop communicating with the network gateway ECU for 3 seconds or more will stop being displayed on the Techstream.
      • The driving support ECU assembly checks for proper ECU communication for ECUs that are connected to the sub bus 13 and the results are displayed on the Techstream. ECUs that stop communicating with the network gateway ECU for 3 seconds or more will stop being displayed on the Techstream.
      • The certification ECU (smart key ECU assembly) checks for proper ECU communication for ECUs that are connected to the sub bus 15 and the results are displayed on the Techstream. ECUs that stop communicating with the network gateway ECU for 3 seconds or more will stop being displayed on the Techstream.
      • w/o Dynamic Rear Steering System:
        • The network gateway ECU checks for proper ECU communication for ECUs that are connected to the sub bus 2 and the results are displayed on the Techstream. ECUs that stop communicating with the network gateway ECU for 3 seconds or more will stop being displayed on the Techstream.
        • For ECUs connected to sub bus 1, sub bus 2, sub bus 13 and sub bus 15 that are in communication stop mode, refer to the flowchart for DTCs related to the communication stop.
      • w/ Dynamic Rear Steering System:
        • The network gateway ECU checks for proper ECU communication for ECUs that are connected to the sub bus 18 and the results are displayed on the Techstream. ECUs that stop communicating with the network gateway ECU for 3 seconds or more will stop being displayed on the Techstream.
        • The network gateway ECU checks for proper ECU communication for ECUs that are connected to the sub bus 19 and the results are displayed on the Techstream. ECUs that stop communicating with the network gateway ECU for 3 seconds or more will stop being displayed on the Techstream.
        • For ECUs connected to sub bus 1, sub bus 13, sub bus 15, sub bus 18 and sub bus 19 that are in communication stop mode, refer to the flowchart for DTCs related to the communication stop.

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module (Network Gateway ECU) [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module (Main Body ECU) [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module (Parking Assist Bus) [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1103" 

    (Refer to DTC U1103: Lost Communication with Stop and Start Control Module [09/2014 - 10/2015] )

    Result: 

    GO TO "Gateway ECU Communication Stop Mode" 

    (Refer to Gateway ECU Communication Stop Mode [09/2014 - 10/2015] )

    Result: 

    GO TO "PROBLEM SYMPTOMS TABLE" 

    (Refer to PROBLEM SYMPTOMS TABLE [09/2014 - 10/2015] )

    Result: 

    GO TO "DIAGNOSTIC TROUBLE CODE CHART" 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART [09/2014 - 10/2015] )

    Result: 

    GO TO "Open in One Side of CAN Branch Line" 

    (Refer to Open in One Side of CAN Branch Line [09/2014 - 10/2015] )

    Result: 

    See step  11

  11. CHECK RESULT OF COMMUNICATION MALFUNCTION CHECK (SELECT THE MALFUNCTIONING BUS) 
    1. Inspect or repair the probable malfunctioning part based on the check result of step 5 (the step in which checking for communication malfunction DTCs was performed).

      Check Result of Communication Malfunction Check (Select Malfunctioning Bus)

      Result Proceed to
      While a DTC indicating a communication malfunction is not being output by a sub bus monitor ECU, the ECUs connected to the V bus have stored DTCs indicating a communication malfunction A
      • w/o Dynamic Rear Steering System:
        1. DTC U1002 (CAN gateway network communication malfunction) is output by the network gateway ECU (the sub bus 2 main line has an open or short circuit)
      • w/ Dynamic Rear Steering System:
        1. DTC U1002 (CAN gateway network communication malfunction) is output by the network gateway ECU (the sub bus 18 main line has an open or short circuit)
      B
      DTC U1002 (network communication malfunction) is output by the network gateway ECU (the sub bus 19 main line has an open or short circuit) C
      DTC U1002 (network communication malfunction) is output by the main body ECU (multiplex network body ECU) (the sub bus 1 main line has an open or short circuit) D
      DTC U1002 (network communication malfunction) is output by the driving support ECU assembly (the sub bus 13 main line has an open or short circuit) E
      DTC U1103 (network communication malfunction) is output by the certification ECU (smart key ECU assembly) (the sub bus 13 main line has an open or short circuit) F
      • w/o Dynamic Rear Steering System:
        1. While DTC U1002 (CAN gateway network communication malfunction) is not being output by the network gateway ECU, DTCs indicating a malfunction in communication with ECUs (sensors) connected to sub bus 2 are output (a malfunction in the branch line for ECUs connected to sub bus 2 or a loss of communication)
      • w/ Dynamic Rear Steering System:
        1. While DTC U1002 (CAN gateway network communication malfunction) is not being output by the network gateway ECU, DTCs indicating a malfunction in communication with ECUs (sensors) connected to sub bus 18 are output (a malfunction in the branch line for ECUs connected to sub bus 18 or a loss of communication)
      • While DTC U1002 (network communication malfunction) is not being output by the network gateway ECU, DTCs indicating a malfunction in communication with ECUs (sensors) connected to sub bus 19 are output (a malfunction in the branch line for ECUs connected to sub bus 19 or a loss of communication)
      • While DTC U1002 (network communication malfunction) is not being output by the main body ECU (multiplex network body ECU), DTCs indicating a malfunction in communication with ECUs (sensors) connected to sub bus 1 are output (a malfunction in the branch line for ECUs connected to sub bus 1 or a loss of communication)
      • While DTC U1002 (network communication malfunction) is not being output by the driving support ECU assembly, DTCs indicating a malfunction in communication with ECUs (sensors) connected to sub bus 13 are output (a malfunction in the branch line for ECUs connected to sub bus 13 or a loss of communication)
      • While DTC U1103 (network communication malfunction) is not being output by the certification ECU (smart key ECU assembly), DTCs indicating a malfunction in communication with ECUs (sensors) connected to sub bus 10 are output (a malfunction in the branch line for ECUs connected to sub bus 10 or a loss of communication)
      G

      HINT: 

      • The term "sub bus monitor ECU" refers to a gateway function equipped ECU that is able to monitor a bus and store DTCs.
      • When checking for communication DTCs, refer to How to Interpret Communication DTCs (DTCs that start with U) (Refer to DIAGNOSIS SYSTEM [09/2014 - 10/2015] ).
      • Because a gateway function equipped ECU (sub bus monitor ECU) monitors signals from all ECUs that are connected to its sub bus, a gateway function equipped ECU can detect ECUs with a communication stop more accurately. In this case, perform troubleshooting by referring to the DTC combination table for the sub bus (Refer to DIAGNOSIS SYSTEM [09/2014 - 10/2015] ).
      • If communication DTCs are stored, and all ECUs and sensors connected to the CAN communication system are displayed on the Communication Bus Check (CAN bus check) screen of the Techstream, a past malfunction that is currently not occurring is suspected.
      • Malfunctions in a branch line of the V bus are detected by the corresponding ECUs (sensors). Therefore, determine the location of the malfunction using the combination of output DTCs.
      • In order to check for malfunctions in sub bus 1, the main body ECU (multiplex network body ECU) checks for a loss of communication and other network communication problems with connected ECUs and stores DTCs when necessary.
      • In order to check for malfunctions in sub bus 13, the driving support ECU assembly checks for a loss of communication and other network communication problems with connected ECUs and stores DTCs when necessary.
      • In order to check for malfunctions in sub bus 15, the certification ECU (smart key ECU assembly) checks for a loss of communication and other network communication problems with connected ECUs and stores DTCs when necessary.
      • w/o Dynamic Rear Steering System:
        • In order to check for malfunctions in sub bus 2, the network gateway ECU checks for a loss of communication and other network communication problems with connected ECUs and stores DTCs when necessary.
        • On the Techstream, DTCs related to a malfunction in sub bus 2 are displayed under "Gateway CAN".
      • w/ Dynamic Rear Steering System:
        • In order to check for malfunctions in sub bus 18 and 19, the network gateway ECU checks for a loss of communication and other network communication problems with connected ECUs and stores DTCs when necessary.
        • On the Techstream, DTCs related to a malfunction in sub bus 18 are displayed under "Multi Bus Monitor 1", and DTCs related to a malfunction in sub bus 19 are displayed under "Multi Bus Monitor 2".
      • When both the sub bus monitor ECU and the ECUs connected to the V bus store communication DTCs, check and repair the corresponding sub bus first.

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module (Network Gateway ECU) [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module (Main Body ECU) [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1002" 

    (Refer to DTC U1002: Lost Communication with Gateway Module (Parking Assist Bus) [09/2014 - 10/2015] )

    Result: 

    GO TO "DTC U1103" 

    (Refer to DTC U1103: Lost Communication with Stop and Start Control Module [09/2014 - 10/2015] )

    Result: 

    GO TO DIAGNOSTIC TROUBLE CODE CHART 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART [09/2014 - 10/2015] )

    Result: 

    See step  12

  12. DTC COMBINATION TABLE 
    1. Confirm the problem according to the combination of output DTCs regarding the CAN communication system (Refer to DIAGNOSIS SYSTEM [09/2014 - 10/2015] ).

      Result

      Result Proceed to
      Combination of DTCs is not in DTC Combination Table A
      Combination of DTCs is in DTC Combination Table B

      HINT: 

      CAN communication system history DTCs may indicate the problem if CAN communication system DTCs are output and all ECUs and sensors connected to the CAN communication system are displayed on "CAN Bus Check" of the Techstream.

    Result: 

    GO TO "COMMUNICATION STOP MODE TABLE" 

    (Refer to PROBLEM SYMPTOMS TABLE [09/2014 - 10/2015] )

    Result: 

    See step  13

  13. IDENTIFICATION OF PROBLEM (PAST MALFUNCTION IN MAIN BUS OF V BUS) 
    1. Connect the cable to the negative (-) battery terminal.
    2. Using the Techstream, clear all DTCs.
    3. Perform a malfunction simulation test on all harnesses and connectors related to the V bus CAN main wire.
    4. Check the DTCs that were output as a result of the malfunction simulation test. Then determine the malfunctioning area.

      HINT: 

      If DTCs are output, do not turn the engine switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  14. REPAIR OR REPLACEMENT 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  15

  15. CONFIRMATION TEST 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    END