How To Proceed With Troubleshooting [10/2014 - 09/2017]: Procedure

HINT: 

• If the engine switch can be turned 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 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 on (IG) even though the battery voltage is normal, repair this malfunction before performing troubleshooting.

  Refer to PROBLEM SYMPTOMS TABLE [10/2014 - ]

Result

Result: 

NEXT 

See step  2

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.)

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 site of 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:
   
   

   Symptoms

   Air conditioning system Was the air conditioner operating 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 Smart access system with push-button start Do the entry lock and unlock functions operate Does the smart warning system operate Do the lights turn on 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 ABS warning light SRS warning light EPS warning light SLIP indicator light 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

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 a 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: 

B 

See step  7

Result: 

C 

Refer to Techstream operator's manual 

Result: 

A 

See step  4

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 or sensor itself also causes 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

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

1. Based on the vehicle equipment and specifications, confirm the systems that use CAN communication.

   Refer to DIAGNOSIS SYSTEM [10/2014 - 09/2017]

2. Select "CAN Bus Check" from the screen on the Techstream.

   CAN Bus Check 

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

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 before measuring the resistances of the CAN main wire and the CAN branch wire.
2. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of DLC3

   Standard Resistance

   Tester Connection	Condition	Specified Condition	Proceed to
   I7-6 (CANH) - I7-14 (CANL)	Cable disconnected from negative (-) battery terminal	OK (54 to 69 Ω)	A
   I7-6 (CANH) - I7-14 (CANL)	Cable disconnected from negative (-) battery terminal	NG (Higher than 70 Ω)	B
   I7-6 (CANH) - I7-14 (CANL)	Cable disconnected from negative (-) battery terminal	NG (Below 53 Ω)	C

Result: 

B 

GO TO "Open in CAN Main Wire". Refer to  Open in CAN Main Wire [10/2014 - 09/2017] 

Result: 

C 

GO TO "Short in CAN Bus Lines". Refer to  Short in CAN Bus Lines [10/2014 - 09/2017] 

Result: 

A 

See step  8

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of DLC3

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I7-6 (CANH) - I7-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
   I7-14 (CANL) - I7-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO "Short to B+ in CAN Bus Lines". Refer to  Short to B+ in CAN Bus Line [10/2014 - 09/2017] 

Result: 

OK 

See step  9

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of DLC3

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I7-6 (CANH) - I7-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher
   I7-14 (CANL) - I7-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO "Short to GND in CAN Bus Lines". Refer to  Short to GND in CAN Bus Line [10/2014 - 09/2017] 

Result: 

OK 

See step  10

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).

   CAN Bus Check 

   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
   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 CAN main wire has an open or short circuit)	B
   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 CAN main wire has an open or short circuit)	C
   All ECUs connected to sub bus 1 are not displayed on the screen (Open in main body ECU (multiplex network body ECU) branch lines or main body ECU (multiplex network body ECU) malfunction)	D
   All ECUs connected to sub bus 2 are not displayed on the screen (Open in network gateway ECU branch lines or network gateway ECU malfunction)	E
   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 CAN branch wire of the ECU (sensor) has an open circuit or there is a loss of communication)	F
   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 CAN branch wire 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.	G
   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 CAN branch wire 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.
   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 CAN branch wires of the ECU [sensor] has an open circuit)	H

   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 Check Screen.

     Refer to DIAGNOSIS SYSTEM [10/2014 - 09/2017]

   • If the detection status of ECUs changes during the inspection, one of the CAN branch wires of a connected ECU or sensor may be open. (Signals from the ECU or sensor that has an open in one of its CAN branch wires create electrical noise, affecting response to the Techstream and whether or not the ECUs and sensors are displayed.)
   • 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 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.

Result: 

B 

GO TO "DTC U1002". Refer to  DTC U1002: Lost Communication with Gateway Module (Main Body) [10/2014 - 09/2016]  , or refer to  DTC U1002: Lost Communication with Gateway Module (Main Body) [09/2016 - 09/2017] 

Result: 

C 

GO TO "DTC U1002". Refer to  DTC U1002: Lost Communication with Gateway Module [10/2014 - 09/2017] 

Result: 

D 

GO TO "Main Body ECU Communication Stop Mode". Refer to  Main Body ECU Communication Stop Mode [10/2014 - 09/2017] 

Result: 

E 

GO TO "Gateway ECU Communication Stop Mode". Refer to  Gateway ECU Communication Stop Mode [10/2014 - 09/2017] 

Result: 

F 

GO TO "PROBLEM SYMPTOMS TABLE". Refer to  PROBLEM SYMPTOMS TABLE [10/2014 - 09/2017]  

Result: 

G 

GO TO "DIAGNOSTIC TROUBLE CODE CHART". Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2014 - 09/2016]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2016 - 09/2017] 

Result: 

H 

GO TO "Open in One Side of CAN Branch Line". Refer to  Open in One Side of CAN Branch Line [10/2014 - 09/2017] 

Result: 

A 

See step  11

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).

   CAN Bus Check 

   Check Result of Communication Malfunction Check (Select Malfunctioning Bus)

   Inspection 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
   DTC U1002 (network communication malfunction) is output by the main body ECU (multiplex network body ECU) (the sub bus 1 CAN main wire has an open or short circuit)	B
   DTC U1002 (network communication malfunction) is output by the network gateway ECU (the sub bus 2 CAN main wire has an open or short circuit)	C
   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 CAN branch wire for ECUs connected to sub bus 1 or a loss of communication)	D
   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 15 are output (a malfunction in the CAN branch wire for ECUs connected to sub bus 15 or a loss of communication)

   HINT: 

   • The term "sub bus monitor ECU" refers to a gateway function equipped ECU that is able to monitor a bus and store DTCs.

     Refer to DIAGNOSIS SYSTEM [10/2014 - 09/2017]

   • When checking for communication DTCs, refer to How to Interpret Communication DTCs (DTCs that start with U).

     Refer to DIAGNOSIS SYSTEM [10/2014 - 09/2017]

   • 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 [10/2014 - 09/2017]

   • 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 CAN branch wire 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 2, the network gateway ECU checks for a loss of communication and other network communication problems with connected ECUs and stores DTCs when necessary.

Result: 

B 

GO TO "DTC U1002". Refer to  DTC U1002: Lost Communication with Gateway Module (Main Body) [10/2014 - 09/2016]  , or refer to  DTC U1002: Lost Communication with Gateway Module (Main Body) [09/2016 - 09/2017] 

Result: 

C 

GO TO "DTC U1002". Refer to  DTC U1002: Lost Communication with Gateway Module [10/2014 - 09/2017] 

Result: 

D 

GO TO "DIAGNOSTIC TROUBLE CODE CHART". Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2014 - 09/2016]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2016 - 09/2017] 

Result: 

A 

See step  12

1. Confirm the problem according to the combination of output DTCs regarding the CAN communication system.

   Refer to DIAGNOSIS SYSTEM [10/2014 - 09/2017]

   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 the CAN Bus Check screen of the Techstream.

   Result

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

Result: 

B 

GO TO COMMUNICATION STOP MODE TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2014 - 09/2017]  

Result: 

A 

See step  13

1. Reconnect the cable to the negative (-) battery terminal.
2. Clear the DTCs using the Techstream.
3. Perform a malfunction simulation test on all harnesses and connectors related to the V bus CAN main wire.
4. 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 engine switch off.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

Result

Result: 

NEXT 

See step  15

Result

Result: 

NEXT 

END