CAN COMMUNICATION SYSTEM(for RHD with Central Gateway ECU) Check Bus 3 Line for Short to +B

DTC Code	DTC Name
	Check Bus 3 Line for Short to +B

DESCRIPTION

There may be a short circuit between one of the CAN bus lines and +B when no resistance exists between terminal 6 (CA3H) of the central gateway ECU and terminal 16 (BAT) of the DLC3, or terminal 21 (CA3L) of the central gateway ECU and terminal 16 (BAT) of the DLC3.


Detection Item	Trouble Area
No resistance exists between terminal 6 (CA3H) of the central gateway ECU and terminal 16 (BAT) of the DLC3, or terminal 21 (CA3L) of the central gateway ECU and terminal 16 (BAT) of the DLC3.	Short to +B in bus 3 CAN main wires Short to +B in bus 3 CAN branch wires Central gateway ECU Navigation receiver assembly1 Radio and display receiver assembly2 No. 8 CAN junction connector

*1: w/ Navigation System

*2: w/ Audio and Visual System (for Radio and Display Type)

WIRING DIAGRAM

CAUTION / NOTICE / HINT

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.
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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 (-) 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 battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work.
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After the repair, perform CAN Bus Check and check that all the ECUs and sensors connected to the CAN communication system are displayed.
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Tip:

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
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.

PROCEDURE

CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 8 CAN JUNCTION CONNECTOR)

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

Disconnect the No. 8 CAN junction connector.

*a	Front view of wire harness connector (to No. 8 CAN Junction Connector)	*b	Front view of DLC3
*c	to Navigation Receiver Assembly (w/ Navigation System) to Radio and Display Receiver Assembly (w/ Audio and Visual System [for Radio and Display Type])	*d	to Central Gateway ECU

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

Standard Resistance


Tester Connection	Condition	Specified Condition	Connect to
G173-1 (CANH) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Navigation receiver assembly1 Radio and display receiver assembly2
G173-12 (CANL) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
G173-3 (CANH) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Central gateway ECU
G173-14 (CANL) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Central gateway ECU
G173-4 (CANH) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Central gateway ECU
G173-15 (CANL) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Central gateway ECU

*1: w/ Navigation System

*2: w/ Audio and Visual System (for Radio and Display Type)

Result


	Proceed to
OK	A
NG (Central gateway ECU CAN main wire)	B
NG (ECU or sensor CAN branch wires)	C

A

REPLACE NO. 8 CAN JUNCTION CONNECTOR

C

CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECU, SENSOR)Click here

B

CONNECT CONNECTOR

Reconnect the G173 No. 8 CAN junction connector.

Result


Proceed to
NEXT

*a	Front view of wire harness connector (to Central Gateway ECU)
*b	Front view of DLC3

Disconnect the central gateway ECU connector.

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

Standard Resistance


Tester Connection	Condition	Specified Condition
G170-6 (CA3H) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
G170-21 (CA3L) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
G170-19 (CAYH) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
G170-20 (CAYL) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

Result


Proceed to
OK
NG

OK

REPLACE CENTRAL GATEWAY ECU

Click here

NG

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CENTRAL GATEWAY ECU - NO. 8 CAN JUNCTION CONNECTOR)

CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECU, SENSOR)

*a	Component with harness connected (Central Gateway ECU)
*b	Front view of DLC3

Reconnect the CAN junction connector.

Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to +B is connected.

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

Standard Resistance


Tester Connection	Condition	Specified Condition
G170-6 (CA3H) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
G170-21 (CA3L) - G14-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

Tip:

If the resistance changes to 6 kΩ or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.

Result


Proceed to
OK
NG

OK

REPLACE CORRESPONDING ECU OR SENSOR

NG

REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRES OR CONNECTOR