CAN Communication System (Diagnostics - Introduction): Overview Toyota Prius C I facelift

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1. NOTICE FOR INITIALIZATION NOTE: When disconnecting the cable from the negative (-) auxiliary battery terminal, initialize the following system after the cable is reconnected. System Name See Procedure Power Door Lock Control System Refer to «INITIALIZATION [12/2013 - ]»(ref-651169-S40634195862014081900000)
2. IGNITION SWITCH EXPRESSIONS The type of ignition switch used on this model differs according to the specifications of the vehicle. The expressions listed in the table below are used in this article. Expression Ignition Switch (Position) Power Switch (Condition) Ignition Switch off LOCK Off (Lock) Ignition Switch ACC ACC On (ACC) Ignition Switch ON ON On (IG) READY ON READY On (READY)
3. CAN COMMUNICATION SYSTEM TROUBLESHOOTING 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. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [12/2013 - ]»(ref-651319-S22157269042014081900000) .
4. PRECAUTIONS FOR STEERING SYSTEM HANDLING Be careful when replacing parts. Incorrect replacement could affect the performance of the steering system and result in hazardous driving.
5. PRECAUTIONS FOR SRS AIRBAG SYSTEM HANDLING This vehicle is equipped with a Supplemental Restraint System (SRS) which includes parts such as airbags for the driver and front passenger. Failure to carry out service operations in the correct sequence could cause unexpected SRS deployment during servicing and may cause a serious accident. Before servicing (including removal or installation of parts, inspection or replacement), be sure to read Precaution for SRS. Refer to «PRECAUTION [12/2013 - ]»(ref-651349-S24445343132014081900000) . HINT: See Supplemental Restraint Systems.
6. BUS LINE REPAIR After repairing a bus line with solder, wrap the repaired part with electrical tape. NOTE: The CANL bus line and CANH bus line must be installed together at all times. When installing, make sure that these lines are twisted, because CAN bus lines are likely to be influenced by electrical noise if the bus lines are not twisted. Leave approximately 80 mm (3.15 in.) loose in the twisted wires around the connector. When repairing the CAN bus lines, do not change the length of the lines. (Make sure that the length of the CANH bus line and CANL bus line are the same.) Do not use bypass wiring between connectors. TEXT IN ILLUSTRATION *a Bypass Wire NOTE: The ability of the twisted bus lines to resist interference will be lost if bypass wiring is used. Do not use a twisted pair of wires for bypass wiring.
7. CONNECTOR HANDLING When checking resistance with a tester, insert the tester probes from the backside (harness side) of the connector. TEXT IN ILLUSTRATION *a Tester Probe Use service wires to check the connector if it is impossible to check continuity from the rear of the connector. TEXT IN ILLUSTRATION *a Service Wire
8. PRECAUTIONS FOR INSPECTING OR REPLACING CAN JUNCTION CONNECTOR If the CAN junction connector is removed from the vehicle for inspection or replacement, make sure to install the CAN junction connector and all wire harnesses to their original locations with tape and the clamps.

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1. OVERALL CAN BUS DIAGRAM Control system CAN is composed of 2 buses. TEXT IN ILLUSTRATION *A w/ Smart Key System *B for Radio and Display Type *1 V Bus *2 Sub Bus 15 *3 V Bus Terminating Resistor *4 Sub Bus 15 Terminating Resistor *5 ECM (for V Bus and Sub Bus 15) *6 Main Body ECU (Multiplex Network Body ECU) (for V Bus) *7 Airbag Sensor Assembly (for V Bus) *8 Spiral Cable with Sensor Sub-assembly (Steering Sensor) (for V Bus) *9 Power Steering ECU Assembly (for V Bus) *10 Air Conditioning Amplifier Assembly (for V Bus) *11 Power Management Control ECU (for V Bus and Sub Bus 15) *12 Smart Key ECU Assembly (Certification ECU) (for V Bus) *13 Brake Booster with Master Cylinder Assembly (Skid Control ECU) (for V Bus and Sub Bus 15) *14 DLC3 (for V Bus) *15 Radio and Display Receiver Assembly (for V Bus) *16 Combination Meter Assembly (for V Bus) HINT: Refer to the following bus wiring diagrams for details.
2. V BUS HINT: The CAN communication system connects to other network via ECUs that function as a gateway. Refer to «SYSTEM DIAGRAM [12/2013 - ]»(ref-651382-S30831402952014081900000) .
3. SUB BUS 15

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1. BRIEF DESCRIPTION The Controller Area Network (CAN) is a serial data communication system for real time application. It is a vehicle multiplex communication system which has a high communication speed and the ability to detect malfunctions. Using the CANH and CANL bus lines as a pair, CAN communication is performed using a voltage differential. (A base voltage is applied to the pair of lines and a voltage differential is created when communicating.) Many ECUs or sensors installed on the vehicle operate by sharing information and communicating with each other. The CAN has two resistors of 120 ohms which are necessary to enable communication. Control system CAN is composed of 3 buses.
2. DEFINITION OF TERMS Main bus The main bus is a wire harness between the two terminating resistors on the bus. This is the main bus in the CAN communication system. Branch A branch is a wire harness which diverges from the main bus to an ECU or sensor. Terminating resistors Two resistors of 120 ohms are installed in parallel across the ends of the CAN main bus lines. They are called terminating resistors. These resistors allow the changes of the voltage differential between the CAN bus lines to be accurately judged. To allow proper function of CAN communication, it is necessary to have both terminating resistors installed. Since the two resistors are installed in parallel, this results in a measurement of approximately 60 ohms.
3. ECUS OR SENSORS WHICH COMMUNICATE THROUGH CAN COMMUNICATION SYSTEM V Bus ECM Brake booster with master cylinder assembly (Skid control ECU) Main body ECU (Multiplex network body ECU) Air conditioning amplifier assembly Power steering ECU assembly Smart key ECU assembly (Certification ECU)*1 Airbag sensor assembly Spiral cable with sensor sub-assembly (Steering sensor) Power management control ECU Combination meter assembly Radio and display receiver assembly*2 HINT: *1: w/ Smart key system *2: for Radio and display type Sub Bus 15 ECM Power management control ECU Brake booster with master cylinder assembly (Skid control ECU)
4. CIRCUIT DESCRIPTION The V bus and sub bus 15 each have termination circuits with two resistors of 120 ohms.
5. TROUBLESHOOTING REMARKS DTCs for the CAN communication system can be checked using the Techstream. The DLC3 is connected to the CAN communication system, but no DTCs exist regarding problems in the DLC3 or the DLC3 branch lines. If there is any trouble in the DLC3 or the DLC3 branch lines, ECUs on the CAN cannot output DTCs to the Techstream. Trouble in the CAN V bus (communication lines) can be checked by measuring the resistance between terminals of the DLC3. However, an open circuit in a branch line other than the DLC3 branch lines cannot be checked from the DLC3 (except branch line of the DLC3). NOTE: Do not insert the tester probes directly into the DLC3. Be sure to use service wires.
6. DIAGNOSTIC TROUBLE CODES FOR CAN COMMUNICATION SYSTEM HINT: See Diagnosis System. Refer to «DIAGNOSIS SYSTEM [12/2013 - ]»(ref-651319-S26839431822014081900000) .
7. HOW TO DISTINGUISH CONNECTOR OF CAN JUNCTION CONNECTOR In the CAN communication system, the shape of connectors connected to the CAN junction connector which has an earth terminal is the same. The connectors connected to the CAN junction connector can be distinguished by the colors of the bus lines and the connecting side of the junction connector. HINT: See Terminals of ECU for bus line color or the shape of connecting surface. Refer to «TERMINALS OF ECU [12/2013 - ]»(ref-651319-S00679558572014081900000) .

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1. PRECAUTIONS WHEN TROUBLESHOOTING NOTE: 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. If the CAN communication system is malfunctioning, check the contact pressure of the terminals in connectors, as insufficient terminal contact pressure may be the cause. Refer to «ELECTRONIC CIRCUIT INSPECTION PROCEDURE [12/2013 - ]»(ref-651169-S28982231602014081900000) . Refer to Diagnosis System for the DTCs for the CAN communication system. Refer to troubleshooting of each system if DTCs regarding the CAN communication system are not output. 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 (-) auxiliary 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 (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work. Refer to «INITIALIZATION [12/2013 - ]»(ref-651169-S40634195862014081900000) . CAN communication DTCs are output for CAN main bus and CAN branch malfunctions as well as for internal malfunctions or power source malfunctions of ECUs or sensors for systems using CAN communication. Therefore, when DTCs for internal malfunctions or power source malfunctions of corresponding systems are output at the same time as CAN communication DTCs, troubleshoot according to the internal malfunction and power source malfunction DTCs. The DLC3 branch and V bus main bus circuits can be checked for malfunctions by inspecting at the DLC3 terminals using a electrical tester. NOTE: When inspecting at the DLC3 connector, do not connect the tester directly to the terminals. Instead, connect using service wires. Inspections for an open in an ECU or sensor branch, or inspections for buses other than the V bus cannot be performed from the DLC3. An open in a branch for ECUs or sensors that are connected to the CAN main bus can be checked by performing a CAN bus check using the Techstream. (This inspection is possible when the DLC3 branch and V bus main bus lines are normal.) If the V bus had a communication error, the probable ECU or sensor for which communication stopped can be determined using the combination of communication DTCs (DTCs that start with U) that are output. A malfunction of sub bus 15 can be determined based on the number of DTCs stored by the ECM, power management control ECU and brake booster with master cylinder assembly (skid control ECU). If a sub bus has a communication error, the gateway function equipped ECU (sub bus monitor ECU) detects it and stores DTCs related to the error. HINT: On the Techstream, gateway function equipped ECUs display DTCs for ECUs connected to the sub bus. When an open circuit is detected, before disconnecting related connectors for inspection, push in on the connector body to check that the connector is not loose or disconnected. When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded. VEHICLE BROUGHT TO WORKSHOP HINT: If the ignition switch can be turned on (IG) (the power source mode can be changed 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 ignition switch off until the inspection of the vehicle is finished, as some fail-safe functions are canceled when the ignition switch is turned off. If the ignition switch cannot be turned on (IG) (the power source mode cannot be changed to on (IG)) when the vehicle is brought in, measure the voltage of the auxiliary battery. If the voltage is below 11 V, recharge or replace the auxiliary battery before performing troubleshooting. If the ignition switch cannot be turned on (IG) even though the auxiliary battery voltage is normal, repair this malfunction before performing troubleshooting. Refer to «PROBLEM SYMPTOMS TABLE [12/2013 - ]»(ref-651177-S16852267872014081900000) . NEXT: Go to next step 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.) 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: ignition switch was turned off) POINTS TO BE CONFIRMED Symptom Electric power steering - Normal - A little heavier than usual - There was no assist Air conditioning - Whether the air conditioning system operated - Whether the blower fan operated Cruise-information display or multi-information display items - Whether display items such as drivable mileage and instantaneous fuel economy update stopped Auto lock and unlock operation - Whether the speed linked auto-lock function operated while driving - Whether the unlock function operated when the shift lever was moved to P Wireless door lock function and smart entry function - Whether the lock/unlock function operated - Whether the illumination was turned on when the key was brought into a smart detection area Operation of other systems of concern Meter warning lights Illumination of warning lights and the order in which they illuminated - Master - Check engine (MIL) - ABS - SLIP - Brake - EPS - SRS - Others Meter display - Speedometer - Hybrid system indicator Content displayed on the multi-information display NEXT: Go to next step CHECK TECHSTREAM OPERATION HINT: Read the Techstream operators manual before use. Refer to «GENERAL INFORMATION [12/2013 - ]»(ref-651169-S36066967812014081900000) . Connect the Techstream to the DLC3. Turn the ignition switch ON. Turn the Techstream on. Check that the Techstream and ECUs can communicate with the ignition switch ON. 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 auxiliary 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 the malfunction. Perform the self tests described in the Techstream operators manual. (The Techstream may be malfunctioning or its battery may be discharged.) 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 B --> Go to step g C --> Refer to Techstream operator's manual A: Go to next step CHECK DTC 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 ignition switch ON, 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. Read the freeze frame data using the Techstream and record it. NEXT: Go to next step CHECK COMMUNICATION MALFUNCTION CHECK (CONNECTION STATUS CHECK USING TECHSTREAM) Select "Communication Malfunction Check" from the screen on the Techstream. Record all the DTCs stored for ECUs and sensors. NEXT: Go to next step CHECK CAN BUS CHECK (CONNECTION STATUS CHECK USING TECHSTREAM) Based on the vehicle equipment and specifications, confirm the systems that use CAN communication. Refer to «DIAGNOSIS SYSTEM [12/2013 - ]»(ref-651319-S26839431822014081900000) . Select "CAN Bus Check" from the screen on the Techstream. Observe the screen for approximately 2 minutes to check the ECUs and sensors displayed on the screen. NEXT: Go to next step CHECK DLC3 BRANCH LINE AND V BUS MAIN LINE (CANH - CANL) 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 (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance. HINT: 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. Disconnect the cable from the negative (-) auxiliary battery terminal. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition G4-6 (CANH) - G4-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 ohms TEXT IN ILLUSTRATION *1 DLC3 Result Result Proceed to OK A NG (70 ohms or higher) B NG (Below 54 ohms) C B --> GO TO OPEN IN CAN MAIN BUS LINE. Refer to «Open in CAN Main Bus Line [12/2013 - ]»(ref-651396-S40980342522014081900000) C --> GO TO SHORT IN CAN BUS LINES. Refer to «Check CAN Bus Lines for Short Circuit [12/2013 - ]»(ref-651396-S08133376252014081900000) A: Go to next step CHECK FOR SHORT TO GND IN V BUS (CANH, CANL - CG) Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition G4-6 (CANH) - G4-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 ohms or higher G4-14 (CANL) - G4-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 ohms or higher TEXT IN ILLUSTRATION *1 DLC3 NG --> GO TO SHORT TO GND IN CAN BUS LINE. Refer to «Check CAN Bus Line for Short to GND [12/2013 - ]»(ref-651396-S34007539772014081900000) OK: Go to next step CHECK FOR SHORT TO +B IN V BUS (CANH, CANL - BAT) Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition G4-6 (CANH) - G4-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kohms or higher G4-14 (CANL) - G4-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kohms or higher TEXT IN ILLUSTRATION *1 DLC3 NG --> GO TO SHORT TO +B IN CAN BUS LINE. Refer to «Check CAN Bus Line for Short to +B [12/2013 - ]»(ref-651396-S34171122842014081900000) OK: Go to next step CHECK RESULT OF CAN BUS CHECK (CONNECTION STATUS CHECK USING TECHSTREAM) 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 the CAN communication system are displayed on the screen. (CAN bus circuit is currently normal.) A When the V bus is selected using the drop down list, all the ECUs and sensors connected to the V bus are displayed on the screen, but when sub bus 15 is selected, no connected ECUs or sensors are displayed. (Open or short in sub bus 15 main lines.) B No ECUs or sensors connected to the ECM or sub bus 15 are displayed on the screen. (Open in ECM main lines or ECM malfunction.) C One of the ECUs and sensors connected to the V Bus is not displayed on the screen. (Open in ECU or sensor branch lines, or communication is interrupted.) D One of the ECUs and sensors connected to sub bus 15 is not displayed on the screen. (Open in ECU or sensor branch lines, or communication is interrupted.) E In addition to ECUs and sensors which are connected to the CAN communication system but are not displayed on the screen, there are ECUs or sensors for which the detection status changes (changes between detected and not detected) during the inspection. (Open in one side of ECU or sensor branch lines.) F 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 [12/2013 - ]»(ref-651319-S26839431822014081900000) . If the detection status of ECUs changes during the inspection, one of the branch lines of a connected ECU or sensor may be open. (Signals from the ECU or sensor that has an open in one of its branch lines create electrical noise, affecting response to the Techstream and whether or not the ECUs and sensors are displayed.) Regarding the ECUs connected to sub bus 15, the ECM displays communicating ECUs on the Techstream. If the communication between the ECM and an ECU stops for 3 seconds or more, the ECU will no longer be displayed on the Techstream. B --> GO TO U0100, U0129, U0293. Refer to «DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0129: Lost Communication with Brake System Control Module; DTC U0293: Lost Communication with HV ECU [12/2013 - ]»(ref-651396-S25604664982014081900000) C --> GO TO ECM COMMUNICATION STOP MODE. Refer to «ECM Communication Stop Mode [12/2013 - ]»(ref-651396-S16971102492014081900000) D --> GO TO COMMUNICATION STOP MODE TABLE. Refer to «PROBLEM SYMPTOMS TABLE [12/2013 - ]»(ref-651319-S12859008222014081900000) E --> GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to «DIAGNOSTIC TROUBLE CODE CHART [12/2013 - ]»(ref-651319-S28073246592014081900000) F --> GO TO OPEN IN ONE SIDE OF CAN BRANCH LINE. Refer to «Open in One Side of CAN Branch Line [12/2013 - ]»(ref-651396-S05982453872014081900000) A: Go to next step CHECK RESULT OF CHECK COMMUNICATION MALFUNCTION CHECK (SELECT THE MALFUNCTIONING BUS) 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 The sub bus monitor ECU has not output communication DTCs but ECUs connected to the V bus have stored communication DTCs. (A malfunction occurred in the V Bus.) ECUs connected to sub bus 15 have not output communication DTCs but ECUs connected to the V bus have stored communication DTCs. (A malfunction occurred in the V Bus.) The ECM has not output DTC U0293 (Lost Communication with HV ECU). The power management control ECU has not output DTC U0100 (Lost Communication with ECM/PCM "A") or DTC U0129 (Lost Communication with Brake System Control Module (U0129)). The brake booster with master cylinder assembly (skid control ECU) has not output DTC U0293 (Lost Communication with HV ECU) A ECUs connected to sub bus 15 store communication error DTCs. (A malfunction occurred in sub bus 15.) The ECM outputs only DTC U0293 (Lost Communication with HV ECU). The power management control ECU outputs only DTC U0100 (Lost Communication with ECM/PCM "A") and DTC U0129 (Lost Communication with Brake System Control Module). The brake booster with master cylinder assembly (skid control ECU) outputs only DTC U0293 (Lost Communication with HV ECU). B The power management control ECU outputs only DTC U0129 (Lost Communication with Brake System Control Module). (A malfunction occurred in an ECU branch line connected to sub bus 15.) C HINT: When checking for communication DTCs, refer to How to Interpret Communication DTCs (DTCs that start with U). Refer to «DIAGNOSIS SYSTEM [12/2013 - ]»(ref-651319-S26839431822014081900000) . 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. When a CAN branch of the V bus is malfunctioning, because the ECUs and sensors related to it detect the malfunction, the problem area can be determined using the combination of DTCs that are output. B --> GO TO U0100, U0129, U0293. Refer to «DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0129: Lost Communication with Brake System Control Module; DTC U0293: Lost Communication with HV ECU [12/2013 - ]»(ref-651396-S25604664982014081900000) C --> GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to «DIAGNOSTIC TROUBLE CODE CHART [12/2013 - ]»(ref-651319-S28073246592014081900000) A: Go to next step DTC COMBINATION TABLE Confirm the problem according to the combination of output DTCs regarding the CAN communication system. Refer to «DIAGNOSIS SYSTEM [12/2013 - ]»(ref-651319-S26839431822014081900000) . 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. B --> GO TO COMMUNICATION STOP MODE TABLE. Refer to «PROBLEM SYMPTOMS TABLE [12/2013 - ]»(ref-651319-S12859008222014081900000) A: Go to next step IDENTIFICATION OF PROBLEM (PAST MALFUNCTION IN MAIN BUS OF V BUS) Connect the cable to the negative (-) auxiliary battery terminal. Clear the DTCs using the Techstream. Perform the tests in Symptom Simulation to check the wire harnesses and connectors including those for V bus main bus lines. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [12/2013 - ]»(ref-651169-S20338414212014081900000) . Based on the results of the check, inspect the parts that output DTCs to determine the malfunctioning part. HINT: If DTCs are output, do not turn the ignition switch off. NEXT: Go to next step REPAIR OR REPLACEMENT NEXT: Go to next step CONFIRMATION TEST NEXT --> END