CAUTION / NOTICE / HINT PRECAUTIONS WHEN TROUBLESHOOTING
NOTICE:
- 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.
Click here 
- 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
or any 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 engine 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
(a)
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. (b) The DLC3
inspection can only be used to detect malfunctions in the diagnosis bus
(the bus which connects the DLC3 to the central gateway ECU (network
gateway ECU)). (c) 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 all the main bus lines are normal.) (d)
In the event of communication error history in the central bus,
identify the ECUs or sensors which were not communicating by analyzing
the combination of stored DTCs or by performing Communication Bus Check
(Detail). (e) 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.
(f)
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. (g) When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded. PROCEDURE
| 1. |
VEHICLE BROUGHT TO WORKSHOP |
HINT:
- If the engine switch can be turned to ON (the power source mode can be
changed to on) 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 (the power source mode
cannot be changed to on) 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 (the power source mode
cannot be changed to on) even though the battery voltage is normal,
repair this malfunction before performing troubleshooting.
Click here
|
NEXT |
 | |
| 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 to
the customer that the additional devices will be removed before
performing troubleshooting as the malfunction cannot be checked
properly.)
- Examples of points to be confirmed are shown below.
(a) 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.)
- Conditions when vehicle returned to normal (engine switch was turned off, etc.)
Points to be confirmed |
Symptom |
- Air conditioning
- Whether the air conditioning system operated
- Whether the blower fan operated
- The air conditioning functions cannot be operated at all
- Electric power steering
- Normal
- A little heavier than usual
- There was no assist
- Drive monitor display
- Whether the update of multi-information display items stopped
- Whether the numeric part of the drivable distance was displayed
- Not displayed at all
- Eco navigation (eco drive) display
- Whether the average fuel consumption graph is updated every minute
- Whether the updated section average fuel consumption graph is displayed
- Whether the distance-to-empty is displayed on the section average fuel consumption graph display
- Not displayed at all
- Interior lights
- Whether the interior light illumination changes when the door is opened or closed
- Whether the interior lights turned off when the engine switch is turned on (IG)
- Not illuminated at all
- Wireless door lock function and smart entry function
- Whether the lock/unlock function operated
- Whether the entry warning function operated
- Whether the illumination was turned on when the key was brought into a smart detection area
- 4WD/AWD operation
- Normal
- Slip detected when starting off
- Memory call
- Normal
- Memory write error
- Memory read error
- Whether the auto return or auto away control is performed
- Operation of other systems of concern
| | Meter warning lights |
- Illumination of warning lights and the order in which they illuminated
- Master
- Check engine (MIL)
- Brake
- ABS
- Slip
- EPS
- SRS
- Others
- Meter display
- Speedometer
- Tachometer
- Engine coolant temperature gauge
- Content displayed on the multi-information display
- Whether the odometer to TRIP meter has stopped
- Whether the value of the average fuel economy is displayed on the multi-information display
- Whether a warning message is displayed on the multi-information display
|
|
NEXT | |
| |
(a) Measure the battery voltage with the engine switch off.
Standard Voltage: 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.
HINT:
- It can be determined if the battery is completely drained by operating the horn.
- If the engine switch cannot be turned on (IG), measure the voltage of
the battery. If it is below 11 V, perform inspection after replacing or
recharging the battery.
- If the engine switch cannot be turned on (IG) even though the battery
voltage is normal, repair this malfunction before performing
troubleshooting.
Click here
| NG |
 | CHARGE OR REPLACE BATTERY |
|
OK | |
| |
| 4. |
CHECK HARNESS AND CONNECTOR (BAT - GROUND) |
| (a) Measure the voltage according to the value(s) in the table below.
Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
G45-16 (BAT) - Body ground |
Always | 11 to 14 V | |
|
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
OK | |
| |
| 5. |
CHECK HARNESS AND CONNECTOR (CG - GROUND) |
| (a) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
G45-4 (CG) - Body ground |
Always | Below 1 Ω | |
|
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
OK | |
| |
| 6. |
CHECK TECHSTREAM OPERATION | HINT:
Read the Techstream operator's manual before use. Click here
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG). (c) Turn the Techstream on.
(d) Check that the Techstream and ECUs can communicate with the engine switch on (IG).
HINT:
- ECUs and sensors are not displayed on the "Communication Bus Check"
screen when the Techstream cannot communicate with the vehicle.
- If communication between the Techstream and ECUs is not possible, either the Techstream or vehicle has a malfunction.
- If communication between the Techstream and ECUs is still not possible
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 | Proceed to | |
OK (Communication between the Techstream and the vehicle is possible.) |
A | | OK
(Communication between the Techstream and the vehicle is not possible
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 15 |
| C |
| REFER TO TECHSTREAM OPERATOR'S MANUAL |
|
A | |
| |
| 7. |
CHECK DTC (HEALTH CHECK) | (a) Using the Techstream, perform Health Check to read current and history DTCs and record them.
NOTICE:
- 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 or sensor itself
also cause these DTCs to be output.
- If a CAN communication line connector is disconnected with the engine
switch on (IG or ACC), the ECUs of the corresponding system and related
systems store a DTC.
HINT: If an
open occurs in just one of the wires of a CAN branch line, 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. (b) Read the freeze frame data using the Techstream and record it.
|
Result | Proceed to | |
OK (Only CAN communication DTCs are output.) |
A | | NG (DTCs other than CAN communication DTCs are also output.) |
B |
| B |
| GO TO DIAGNOSTIC TROUBLE CODE CHART OF RELATED SYSTEM |
|
A | |
| |
| 8. |
CHECK FOR DTCS (IDENTIFY ABNORMAL BUS) |
(a) Proceed to the "Communication Malfunction Check" screen from the "Communication Bus Check" screen.
(b) Record all the DTCs stored for ECUs and sensors. (c) Check if the stored DTCs are listed in the Diagnostic Trouble Code Chart of the CAN Communication System.
Click here
HINT:
- For details on how to change to and from the "Communication Malfunction
Check" screen, refer to Communication Bus Check (Communication
Malfunction Check).
Click here
- For the definition of central bus, sub bus and local bus, refer to Definition of Terms.
Click here
- A sub bus monitoring ECU is a gateway function equipped ECU that monitors ECUs and sensors on its respective bus.
- When the vehicle is equipped with a sub bus, refer to System Diagram to confirm the sub bus monitoring ECU.
Click here
- Sub bus monitoring ECUs monitor all ECUs and sensors connected to their
respective sub bus and can accurately detect when an ECU or sensor stops
communicating.
- When CAN communication DTCs are stored but all ECUs and sensors
connected to the CAN communication system are displayed as normal on the
"Communication Bus Check" screen of the Techstream, a past malfunction
is suspected.
- When a sub bus monitoring ECU detects a communication error in the
network, or that an ECU or sensor has stopped communicating, it stores a
DTC.
- When CAN communication DTCs are stored in an ECU connected to the
central bus and in a sub bus monitoring ECU, inspect the corresponding
sub bus and perform repairs if necessary before inspecting the central
bus.
- A malfunctioning local bus will not affect the central bus or sub buses.
- When CAN communication DTCs are stored for a local bus, inspect related systems and perform repairs if necessary.
|
Result | Proceed to | |
The stored DTCs are not listed in the Diagnostic Trouble Code Chart for CAN Communication System. |
A | | The stored DTCs are listed in the Diagnostic Trouble Code Chart for CAN Communication System. |
B |
| B |
| GO TO DIAGNOSTIC TROUBLE CODE CHART |
|
A | |
| |
| 9. |
BUS INSPECTION (CHECK CONNECTED ECUS AND SENSORS USING TECHSTREAM) |
(a) Based on the vehicle equipment and specifications, confirm the systems that use CAN communication.
Click here (b) Select "CAN Bus Check" from the screen on the Techstream.
(c) Observe the screen for approximately 2 minutes to check the ECUs and sensors displayed on the screen.
(d) Check for ECUs or sensors with a background color that indicates that they are currently not communicating.
NOTICE:
- A sub bus monitoring ECU outputs DTCs for its respective ECUs and
sensors. Identify the malfunctioning ECU or sensor using the output
DTCs.
- ECUs or sensors that are not installed to the vehicle will not be
displayed. Do not mistake these for ECUs or sensors that are not
communicating.
- When using the combo box, it may be possible to select a sub bus from
the drop down list that does not have any connected ECUs or sensors.
This is not a malfunction and occurs when there is no optional device
connected to a sub bus which is monitored by a sub bus monitoring ECU
(gateway function equipped ECU).
HINT:
- For details on how to read the "Communication Bus Check" screen, refer to Description of "Communication Bus Check" screen.
Click here
- If there is an ECU or sensor whose connection status changes
intermittently while checking the "Communication Bus Check" screen,
there may be an open circuit in one of the wires of a branch line of an
ECU or sensor in the bus. If an open occurs in one of the wires of a CAN
branch line, it may interfere with the communication of other ECUs or
sensors resulting in an incorrect state being displayed.
- The central gateway ECU (network gateway ECU) displays the connection
status of ECUs and sensors connected to the central bus on the
Techstream.
- Sub bus monitoring ECUs display the connection status of ECUs and
sensors connected to their respective sub bus on the Techstream.
- If a CAN commutation DTC is output for an ECU connected to the sub bus, refer to the corresponding diagnostic procedure.
Click here
|
Result | Proceed to | |
An ECU or sensor is not communicating (An ECU or sensor has a red or red and yellow background) |
A | | All ECU and sensors are communicating
(All ECUs or sensors have a white or white and yellow background) |
B |
| B |
| GO TO STEP 12 |
|
A | |
| |
| 10. |
CONFIRM PROBLEM SYMPTOMS (CHECK CONNECTED ECUS AND SENSORS USING TECHSTREAM) |
(a)
Confirm the suspected cause of the problem symptoms by referring to How
to Use "Communication Bus Check" Screen in Inspection and using the
result of Bus Inspection (Check Connected ECUs and Sensors Using
Techstream).
HINT:
- For details on how to inspect buses, refer to How to Use "Communication Bus Check" Screen in Inspection.
Click here
- If there are multiple ECUs or sensors that are not communicating, check for blown fuses before proceeding with troubleshooting.
- If there are multiple ECUs or sensors that are not communicating, after
confirming that there are no power supply malfunctions, check for an
open in CAN bus main lines, a short in CAN bus lines (CANH or CANL) or a
short to ground or +B in CAN bus lines.
- If there is an ECU or sensor that is not communicating, there may be an
open circuit in one of the wires of its branch line. In this situation,
the malfunctioning wire harness may affect noise immunity and interfere
with the communication of other ECUs or sensors on the same bus. This
may affect the validity of the displayed data.
|
Result | Proceed to | |
The problem symptom is found in the table for Problem Symptom Patterns other than Patterns A or B. |
A |
- The problem symptom is not found in Problem Symptoms Table in How to Use "Communication Bus Check" Screen in Inspection.
- The problem symptom is found in the table for Problem Symptom Patterns A or B.
| B |
| A |
| GO TO PROBLEM SYMPTOMS TABLE |
|
B | |
| |
| 11. |
CAN BUS INSPECTION (DETERMINE CAUSE OF PROBLEM SYMPTOM) |
(a) Disconnect the cable from the negative (-) battery terminal. (b)
Measure the resistance of any suspected buses that were specified by
the result of Confirm Problem Symptoms (Check Connected ECUs and Sensors
Using Techstream).
HINT:
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | Result | |
CANH - CANL of a suspected bus |
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 main bus lines | |
CANH - body ground of a suspected bus |
Cable disconnected from negative (-) battery terminal |
200 Ω or higher | Below 200 Ω: CANH short to ground | |
CANL - body ground of a suspected bus |
Cable disconnected from negative (-) battery terminal |
200 Ω or higher | Below 200 Ω: CANL short to ground | |
CANH - +B of a suspected bus |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher | Below 6 kΩ: CANH +B short | |
CANL - +B of a suspected bus |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher | Below 6 kΩ: CANL +B short |
|
Result | Proceed to | |
OK (CAN bus main lines are normal) |
Go to Inspection for Open Circuit in a Branch Line | |
NG (There is an open or short in a CAN bus main line of a suspected bus) |
Go to Respective Inspection |
| Go to Inspection for Open Circuit in a Branch Line |
| GO TO PROBLEM SYMPTOMS TABLE |
| Go to Respective Inspection |
| GO TO PROBLEM SYMPTOMS TABLE |
| 12. |
BUS INSPECTION (DETAIL) (CHECK CONNECTED ECUS AND SENSORS USING TECHSTREAM) |
(a) Using the Techstream, display the "Communication Bus Check (Detail)" screen.
HINT: For
details on how to inspect buses using the "Communication Bus Check
(Detail)" screen, refer to Description of "Communication Bus Check"
Screen. Click here (b) Check the display for ECUs or sensors which have communication error history.
NOTICE:
- ECUs or sensors that are not installed to the vehicle will not be
displayed. Do not mistake these for ECUs or sensors that are not
communicating.
- When using the combo box, it may be possible to select a sub bus from
the drop down list that does not have any connected ECUs or sensors.
This is not a malfunction and occurs when there is no optional device
connected to a sub bus which is monitored by a sub bus monitoring ECU
(gateway function equipped ECU).
HINT:
- The communication history of ECUs or sensors which have communication
error history can be displayed on the "Communication Bus Check (Detail)"
screen.
- Lost Communication Time and Lost Communication Trip are only displayed for the central bus.
- Lost Communication Time and Lost Communication Trip are not displayed for sub buses.
(c) Check for ECUs or sensors with a red background.
|
Result | Proceed to | |
An ECU or sensor has communication stop history. (The background color of an ECU or sensor is red.) |
A | | No ECUs or sensors have communication stop history.
(The background color of an ECU or sensor is not red.) |
B |
| B |
| GO TO STEP 14 |
|
A | |
| |
| 13. |
CONFIRM PROBLEM SYMPTOMS (CHECK CONNECTED ECUS AND SENSORS USING TECHSTREAM) |
(a)
Confirm the suspected cause of the problem symptoms by referring to How
to Use "Communication Bus Check (Detail)" Screen in Inspection and
using the result of Bus Inspection (Detail) (Check Connected ECUs and
Sensors Using Techstream).
NOTICE:
- ECUs or sensors that are not installed to the vehicle will not be
displayed. Do not mistake these for ECUs or sensors that are not
communicating.
- When using the combo box, it may be possible to select a sub bus from
the drop down list that does not have any connected ECUs or sensors.
This is not a malfunction and occurs when there is no optional device
connected to a sub bus which is monitored by a sub bus monitoring ECU
(gateway function equipped ECU).
HINT:
- For details on "Communication Bus Check (Detail)" screen, refer to How
to Use "Communication Bus Check (Detail)" Screen in Inspection.
Click here
- Lost Communication Time and Lost Communication Trip are only displayed for the central bus.
- Lost Communication Time and Lost Communication Trip are not displayed for sub buses.
- If an ECU or sensor has communication stop history, the background color of the ECU or sensor will be red.
- If more than one ECU or sensor has a background color of red, check the
values of Lost Communication Trip and Lost Communication Time.
Communication error of an ECU or sensor with the value of Lost
Communication Trip closest to the Current Trip and the largest value of
Lost Communication Time is suspected.
|
Result | Proceed to | |
Suspected cause of problem symptom is found. |
A | | Suspected cause of problem symptom is not found. |
B |
| A |
| GO TO PROBLEM SYMPTOMS TABLE |
|
B | |
| |
| 14. |
CHECK DTC COMBINATION TABLE | (a) Determine the ECUs or sensors that were not communicating based on the combination of DTCs output from each ECU.
Click here
|
Result | Proceed to | |
Combination of DTCs is not in DTC Combination Table |
A | | Combination of DTCs is in DTC Combination Table |
B |
| A |
| INSPECT FOR INTERMITTENT PROBLEMS |
| B |
| INSPECT PROBLEMS ACCORDING TO DTC COMBINATION TABLE |
| 15. |
CHECK HARNESS AND CONNECTOR (DLC3 - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
NOTICE: 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 or any
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. (a) Disconnect the cable from the negative (-) battery terminal.
| (b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
G45-6 (CANH) - G45-14 (CANL) |
Cable disconnected from negative (-) battery terminal |
54 to 69 Ω | |
G45-6 (CANH) - G45-4 (CG) |
Cable disconnected from negative (-) battery terminal |
200 Ω or higher | |
G45-14 (CANL) - G45-4 (CG) |
Cable disconnected from negative (-) battery terminal |
200 Ω or higher | |
G45-6 (CANH) - G45-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher | |
G45-14 (CANL) - G45-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher | HINT: If
the resistance between CANH and CANL is not as specified, a connector
may have been loose or disconnected during inspection. If a connector is
loose or disconnected, connect it and perform the inspection again. |
|
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (DLC3 - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
|
OK | |
| |
| 16. |
CHECK HARNESS AND CONNECTOR (GROUND CIRCUIT) |
(a) Disconnect the G52 central gateway ECU (network gateway ECU) connector.
| (b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
G52-10 (GND) - Body ground |
Cable disconnected from negative (-) battery terminal |
Below 1 Ω | |
 |
|
*a | Front view of wire harness connector
(to Central Gateway ECU (Network Gateway ECU)) | | |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (GND TERMINAL) |
|
OK | |
| |
| 17. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) |
(a) Reconnect the cable to the negative (-) battery terminal.
| (b) Measure the voltage according to the value(s) in the table below.
Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
G52-1 (BATT) - Body ground |
Always | 11 to 14 V | |
G52-2 (ACC) - Body ground |
Engine switch on (ACC) |
11 to 14 V | |
G52-11 (IG1) - Body ground |
Engine switch on (IG) |
11 to 14 V | |
G52-12 (IG2) - Body ground |
Engine switch on (IG) |
11 to 14 V | |
 |
|
*a | Front view of wire harness connector
(to Central Gateway ECU (Network Gateway ECU)) | | |
| OK |
| REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) | |
