How To Proceed With Troubleshooting [10/2013 - ]

WARNING: This page is about a different variant/trim than selected.

NOTE:

DTCs for the CAN communication system are as follows: U0073, U0100, U0101, U0103, U0104, U0122, U0123, U0124, U0126, U0129, U0131, U0140, U0142, U0146, U0151, U0155, U0164, U0198, U019B, U0235, U0293, U0327, U1002, U1100, U1104, U1107, U1133 and U1135.
Refer to troubleshooting of each system if DTCs regarding the CAN communication system are not output.

HINT:

*: Use the Techstream.

VEHICLE BROUGHT TO WORKSHOP
NEXT: Go to next step
CUSTOMER PROBLEM ANALYSIS
1. Interview the customer and confirm the problem.
  NEXT: Go to next step
CHECK AUXILIARY BATTERY
Standard Voltage

11 to 14 V

HINT:

If the voltage is below 11 V, recharge or replace the auxiliary battery before proceeding to the next step.

NEXT: Go to next step
CHECK AND CLEAR DTCS*
HINT:
- CAN communication DTCs are stored when there is an open or short in any of the communication wires. Any problems with the power source of a corresponding ECU or sensor, or problems in the ECU or the sensor itself also cause these DTCs to be stored.
- If a CAN communication wire connector is disconnected with the power switch on (IG), the ECUs of the corresponding system and related systems store a DTC.
NEXT: Go to next step

CHECK FOR DLC3 BRANCH WIRE AND V1 BUS MAIN WIRE (CANH - CANL)

NOTE:

Turn the power switch off before measuring the resistances between CAN main bus wires and between CAN main bus branch wires.
Turn the power switch off before inspecting CAN bus wires for a ground short.
After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT:

Operating the power switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

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

Fig 1: Identifying DLC3 Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
L61-6 (CANH) - L61-14 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	54 to 69 Ω

TEXT IN ILLUSTRATION

DLC3

Result

Result	Proceed to
OK	A
NG (70 Ω or higher)	B
NG (Below 54 Ω)	C

B → GO TO OPEN IN CAN MAIN BUS WIRE. Refer to Open in CAN Main Bus Line [10/2013 - ]

C → GO TO SHORT IN CAN BUS WIRES. Refer to Check CAN Bus Lines for Short Circuit [10/2013 - ]

A: Go to next step

CHECK FOR SHORT TO GND IN V1 BUS (CANH, CANL - CG)

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

Fig 2: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
L61-6 (CANH) - L61-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
L61-14 (CANL) - L61-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher

TEXT IN ILLUSTRATION

DLC3

NG → GO TO SHORT TO GND IN CAN BUS WIRE. Refer to Check CAN Bus Line for Short to GND [10/2013 - ]

OK: Go to next step

CHECK FOR SHORT TO +B IN V1 BUS (CANH, CANL - BAT)

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

Fig 3: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Condition	Specified Condition
L61-6 (CANH) - L61-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher
L61-14 (CANL) - L61-16 (BAT)	Cable disconnected from negative (-) auxiliary battery terminal	6 kΩ or higher

TEXT IN ILLUSTRATION

DLC3

NG → GO TO SHORT TO +B IN CAN BUS WIRE. Refer to Check CAN Bus Line for Short to +B [10/2013 - ]

OK: Go to next step

CHECK INSTALLED SYSTEMS (ECU AND SENSOR) THAT USE CAN COMMUNICATION
1. Based on the vehicle equipment and specifications, confirm the systems that use CAN communication. Refer to DIAGNOSIS SYSTEM [10/2013 - ] .
  NEXT: Go to next step

CHECK ECUS CONNECTED TO CAN BUS*

Select "CAN Bus Check" from the screen on the Techstream. Refer to DIAGNOSIS SYSTEM [10/2013 - ] .

Observe the screen for approximately 1 minute to check the ECUs and sensors displayed on the screen.

Result

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
All ECUs except the power management control ECU connected to the V2 bus are not displayed on the screen. The power management control ECU (power management1) outputs DTC U1002. (Open or short in V2 bus main wires.)	B
When the V1 bus is selected using the drop down list, all the ECUs and sensors connected to the V1 bus are displayed on the screen, but when power management bus is selected, no connected ECUs or sensors are displayed. (Open or short in power management bus main wires.)	C
All ECUs connected to V2 are not displayed on the screen. (Open in power management control ECU branch lines or power management control ECU malfunction.)	D
No ECUs or sensors connected to the ECM or power management bus are displayed on the screen. (Open in ECM main wires or ECM malfunction.)	E
One of the ECUs and sensors connected to the V1 Bus is not displayed on the screen. (Open in ECU or sensor branch wires, or communication is interrupted.)	F
One of the ECUs and sensors connected to V2 bus is not displayed on the screen.* (Open in ECU or sensor branch wires, or communication is interrupted.) One of the ECUs and sensors connected to power management bus is not displayed on the screen. (Open in ECU or sensor branch wires, or communication is interrupted.)	G
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 wires.)	H

NOTE:

*: In this case, as the power management control ECU (PM1 Gateway) outputs communication DTCs (DTCs that start with U), the problem area can be determined from those DTCs.
The systems (ECUs and sensors) that adopt CAN communication vary depending on the vehicle and optional equipment. Check which systems (ECUs and sensors) are installed on the vehicle. Refer to DIAGNOSIS SYSTEM [10/2013 - ] .
Non-installed ECUs or sensors will not be displayed. Do not mistake them for being in communication stop mode.
The ECUs and sensors that repeatedly appear and disappear from the screen during this check are considered normal. (The response to the Techstream and its display are affected by signals output from other ECUs which have an open circuit in either of their CAN main bus branch wires.)

HINT:

The ECUs connected to the V2 bus is displayed on the screen by the power management control ECU.

B → GO TO U1002 (POWER MANAGEMENT1). Refer to DTC U1002: Lost Communication with Gateway Module (Power Management1) [10/2013 - ]

C → 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 [10/2013 - ]

D → GO TO POWER MANAGEMENT CONTROL ECU COMMUNICATION STOP MODE. Refer to Power Management Control ECU Communication Stop Mode [10/2013 - ]

E → GO TO ECM COMMUNICATION STOP MODE. Refer to ECM Communication Stop Mode [10/2013 - ]

F → GO TO COMMUNICATION STOP MODE TABLE. Refer to PROBLEM SYMPTOMS TABLE [10/2013 - ]

G → GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2013 - ]

H → GO TO OPEN IN ONE SIDE OF CAN MAIN BUS BRANCH WIRE. Refer to Open in One Side of CAN Branch Line [10/2013 - ]

A: Go to next step

RECHECK DTC*

HINT:

Sometimes CAN communication system DTCs are output, but all ECUs and sensors connected to the CAN communication system are displayed on the Techstream. In this case, previous or history DTCs may indicate the cause of the problem.
ECUs related to a problem in the CAN bus will store DTCs to indicate communication malfunctions. Communication stop mode in the CAN bus can be determined by comparing the combination of DTCs that have been set. Refer to DTC Combination Table for the CAN bus.
The power management control ECU will store communication error DTCs when the ECUs connected to the V2 bus and cannot communicate, or if a network malfunction occurs.

Result

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 power management bus 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 (Engine and ECT) has not output DTC U0293 (Lost Communication with HV ECU). The power management control ECU (Hybrid Control) has not output DTC U0100 (Lost Communication with ECM/PCM "A") or DTC U0129 (Lost Communication with Brake System Control Module). The brake booster with master cylinder (skid control ECU) (ABS/VSC/TRAC) has not output DTC U0293 (Lost Communication with HV ECU).	A
The power management control ECU (Power Management1) outputs DTC 1002. (A malfunction occurred in the V2 bus.)	B
ECUs connected to power management bus store communication error DTCs. (A malfunction occurred in the power management bus.) The ECM (Engine and ECT) outputs only DTC U0293 (Lost Communication with HV ECU). The power management control ECU (Hybrid Control) 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 (skid control ECU) (ABS/VSC/TRAC) outputs only DTC U0293 (Lost Communication with HV ECU).	C
The power management control ECU (PM1 Gateway) outputs DTCs other than DTC 1002. (A malfunction occurred in an ECU branch wire connected to V2 bus.)	D
The driving support ECU (Pre-Collision2) outputs DTC 1002. (A malfunction occurred in the driving support bus.)	E
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 power management bus.)	F

B → GO TO U1002 (POWER MANAGEMENT1). Refer to DTC U1002: Lost Communication with Gateway Module (Power Management1) [10/2013 - ]

D → GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2013 - ]

E → GO TO U1002 (PARKING ASSIST BUS). Refer to DTC U1002: Lost Communication with Gateway Module (Parking Assist Bus) [10/2013 - ]

F → GO TO U0129. Refer to DTC U0129: Lost Communication with Brake System Control Module [10/2013 - ]

A: Go to next step

DTC COMBINATION TABLE
1. Confirm trouble according to the combination of output DTCs regarding the CAN communication system. Refer to DIAGNOSIS SYSTEM [10/2013 - ] .
  HINT:
  
  Previous CAN communication system DTCs may be the cause 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.
  
  NEXT: Go to next step
CIRCUIT INSPECTION
NEXT: Go to next step
IDENTIFICATION OF PROBLEM
NEXT: Go to next step
REPAIR OR REPLACEMENT
NEXT: Go to next step
CONFIRMATION TEST*
NEXT → END