Short to B+ in CAN Bus Line: Procedure

1. Disconnect the cable from negative (-) battery terminal.
2. Disconnect the DLC3 branch line connector (J8) from the CAN LH J/C B side (w/o earth terminal).
   Fig 1: Identifying CAN LH J/C B Side (w/o earth terminal)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   NOTE:

   • Before disconnecting the connector, make a note of where it is connected.
   • Reconnect the connector to its original position.
3. Measure the resistance according to the value(s) in the table below.
   Fig 2: Identifying DLC3 Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J21-6 (CANH) - J21-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
   J21-14 (CANL) - J21-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

NG → REPAIR OR REPLACE DLC3 BRANCH WIRE OR CONNECTOR 

OK: Go to next step 

1. Reconnect the DLC3 branch line connector (J8) to the CAN LH J/C B side (w/o earth terminal).

NEXT: Go to next step 

1. Disconnect connectors from the CAN LH J/C or CAN RH J/C one at a time.

   HINT: 

   Disconnect the ECU and sensor connectors other than the DLC3 branch lines and CAN main bus lines between the CAN LH J/C and CAN RH J/C.

   Fig 3: Identifying DLC3 Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Using an ohmmeter, measure the resistance between terminals 6 (CANH) and 16 (BAT), and between terminals 14 (CANL) and 16 (BAT) of the DLC3 each time a connector is disconnected.
   Fig 4: Identifying CAN LH J/C Connectors Wiring Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   Fig 5: Identifying CAN LH J/C Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   WIRING COLOR:
   
   

   CAN LH J/C A Side (w/ Earth Terminal)	Code	Color (CANH Side)	Color (CANL Side)
   Steering angle sensor	J1	P	W
   ECM	J2	B	W
   Seat belt control ECU (w/ Pre-collision system)	J3	V	W
   Center airbag sensor	J4	R	W

   WIRING COLOR:
   
   

   CAN LH J/C B Side (w/o Earth Terminal)	Code	Color (CANH Side)	Color (CANL Side)
   Yaw rate sensor	J5	P	W
   Skid control ECU	J6	R	W
   CAN main bus line (bus line connecting CAN LH J/C and CAN RH J/C)	J7	B	W
   DLC3	J8	G	W
   Distance control ECU (w/ Dynamic radar cruise control system)	J9	GR	W

   Fig 6: Identifying CAN RH J/C Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   WIRING COLOR:
   
   

   CAN RH J/C A Side (w/ Earth Terminal)	Code	Color (CANH Side)	Color (CANL Side)
   CAN main bus line (bus line connecting CAN RH J/C and CAN LH J/C)	J81	B	W
   Power steering ECU	J82	P	W

   WIRING COLOR:
   
   

   CAN RH J/C B Side (w/o Earth Terminal)	Code	Color (CANH Side)	Color (CANL Side)
   Gateway ECU	J84	B	W
   4WD control ECU (for 4WD)	J86	V	W

   NOTE:

   Do not reconnect the disconnected connectors until this inspection is complete because there may be a short to B+ in 2 or more CAN bus lines.

   Result

   Symptom	Proceed to
   The resistance between terminals 6 (CANH) and 16 (BAT), or the resistance between 14 (CANL) and 16 (BAT) is still below 6 kΩ when all the specified connectors are disconnected from the CAN J/C. (There is a short to B+ in the CAN main bus lines between the CAN LH J/C and CAN RH J/C.)	A
   The resistance between terminals 6 (CANH) and 16 (BAT), or the resistance between 14 (CANL) and 16 (BAT) becomes normal (6 kΩ or more) when a connector is disconnected from the CAN J/C. (There is a short to B+ in one of the areas that relate to one or more of the disconnected bus lines.)	B

3. When there is a short to B+ in one or more of the bus lines that connect to an ECU (or sensor):
   1. Reconnect all of the connectors to the CAN J/C, except for the one that was disconnected last (the bus line that is shorted to B+). Check that the resistance shown on the tester is normal (6 kΩ or more) to confirm that there is a short to B+ in the one bus line only.

      HINT: 

      • The connectors connected to the CAN J/C can be distinguished according to the color of the communication bus lines and the shape of the connectors.
      • Reconnecting the connectors to non-specified positions on the CAN J/C does not affect system operation. However, it is preferred to reconnect the connectors to their specified positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.

A → REPAIR OR REPLACE CAN BUS MAIN WIRE (CAN LH J/C - CAN RH J/C) 

B: Go to next step 

1. Reconnect the connector of the bus line that is shorted to B+ to the CAN J/C (the connector that caused the bus line resistance to change to 6 kΩ or more when it was disconnected).

NEXT: Go to next step 

1. Disconnect the connector that includes terminals CANH and CANL from the ECU (or sensor) to which the bus line shorted to B+ is connected. Refer to TERMINALS OF ECU .
   Fig 7: Identifying DLC3 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J21-6 (CANH) - J21-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
   J21-14 (CANL) - J21-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

   HINT: 

   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).

NG → REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BUS LINE OR CONNECTOR 

OK → REPLACE CORRESPONDING ECU OR SENSOR