CAN COMMUNICATION SYSTEM Check Bus 5 Line for Short to GND

DESCRIPTION

There may be a short circuit between one of the CAN bus lines and GND when there is no resistance between terminal 15 (CA5H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

Symptom	Trouble Area
No resistance exists between terminal 15 (CA5H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.	Short to ground in CAN main bus line Short to ground in CAN branch line Central gateway ECU (network gateway ECU) Hybrid vehicle control ECU assembly Blind spot monitor sensor LH (w/ Blind Spot Monitor System) Absorber control ECU (w/ AVS System) Driving support ECU assembly (w/ Lexus Safety System +) Millimeter wave radar sensor assembly (w/ Lexus Safety System +) Forward recognition camera (w/ Lexus Safety System +) Clearance warning ECU assembly (w/ LEXUS Parking Assist-sensor System) No. 9 CAN junction connector or No. 10 CAN junction connector No. 12 CAN junction connector No. 13 CAN junction connector

Symptom

Trouble Area

No resistance exists between terminal 15 (CA5H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

Short to ground in CAN main bus line
Short to ground in CAN branch line
Central gateway ECU (network gateway ECU)
Hybrid vehicle control ECU assembly
Blind spot monitor sensor LH

(w/ Blind Spot Monitor System)
Absorber control ECU

(w/ AVS System)
Driving support ECU assembly

(w/ Lexus Safety System +)
Millimeter wave radar sensor assembly

(w/ Lexus Safety System +)
Forward recognition camera

(w/ Lexus Safety System +)
Clearance warning ECU assembly

(w/ LEXUS Parking Assist-sensor System)
No. 9 CAN junction connector or No. 10 CAN junction connector
No. 12 CAN junction connector
No. 13 CAN junction connector

WIRING DIAGRAM

Figure 1. for LHD with No. 9 CAN Junction Connector

Figure 2. for LHD with No. 10 CAN Junction Connector

Figure 3. for RHD with No. 9 CAN Junction Connector

Figure 4. for RHD with No. 10 CAN Junction Connector

CAUTION / NOTICE / HINT

Note

Before measuring the resistance of the CAN bus, turn the power 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 (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here
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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After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

DTC check procedure: Turn the power switch on (IG) and wait at least 36 seconds. Turn the cruise control main switch on, turn the lane departure alert main switch on and then drive the vehicle at a speed of 36 km/h (22 mph) or more for 52 seconds or more.
After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

Click here

Tech Tips

Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

CHECK VEHICLE TYPE

Check vehicle type.

Result

Result	Proceed to
for LHD	A
for RHD	B

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 13 CAN JUNCTION CONNECTOR) Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 13 CAN JUNCTION CONNECTOR)

Disconnect the cable from the negative (-) auxiliary battery terminal.
Disconnect the K151, K152, K153, K154, K155 and K159 No. 13 CAN junction connectors.

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

*1	DLC3	-	-
*a	Rear view of wire harness connector (to No. 13 CAN Junction Connector)	*b	to No. 12 CAN Junction Connector
*c	to Forward Recognition Camera (w/ Lexus Safety System +)	*d	to Millimeter Wave Radar Sensor Assembly (w/ Lexus Safety System +)
*e	to Clearance Warning ECU Assembly (w/ LEXUS Parking Assist-sensor System)	*f	to No. 9 CAN Junction Connector or No. 10 CAN Junction Connector
*g	to Driving Support ECU Assembly (w/ Lexus Safety System +)	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
K151-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 12 CAN junction connector
K151-2 (CANL) - K9-4 (CG)		200 Ω or higher	No. 12 CAN junction connector
K152-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Forward recognition camera*1
K152-2 (CANL) - K9-4 (CG)		200 Ω or higher	Forward recognition camera*1
K153-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Millimeter wave radar sensor assembly*1
K153-2 (CANL) - K9-4 (CG)		200 Ω or higher	Millimeter wave radar sensor assembly*1
K154-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Clearance warning ECU assembly*2
K154-2 (CANL) - K9-4 (CG)		200 Ω or higher	Clearance warning ECU assembly*2
K155-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 9 CAN junction connector or No. 10 CAN junction connector
K155-2 (CANL) - K9-4 (CG)		200 Ω or higher
K159-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Driving support ECU assembly*1
K159-2 (CANL) - K9-4 (CG)		200 Ω or higher	Driving support ECU assembly*1

*1: w/ Lexus Safety System +
*2: w/ LEXUS Parking Assist-sensor System

Result

Result	Proceed to
OK	A
NG (Line to No. 9 CAN junction connector or No. 10 CAN junction connector)	B
NG (Line to No. 12 CAN junction connector)	C
NG (Line to ECU or sensor)	D

REPLACE NO. 13 CAN JUNCTION CONNECTOR

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 12 CAN JUNCTION CONNECTOR) Click here

GO TO STEP 15 Click here

CHECK VEHICLE TYPE

Check whether the No. 9 CAN junction connector or No. 10 CAN junction connector is installed to the vehicle.

Click here

Component with harness connected

(No. 9 CAN Junction Connector)

Front view of wire harness connector

(to No. 10 CAN Junction Connector)

Result

Result	Proceed to
w/ No. 9 CAN Junction Connector	A
w/ No. 10 CAN Junction Connector	B

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 10 CAN JUNCTION CONNECTOR) Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 9 CAN JUNCTION CONNECTOR)

Disconnect the Q63, Q64 and Q65 No. 9 CAN junction connectors.

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

DLC3

Rear view of wire harness connector

(to No. 9 CAN Junction Connector)

to No. 13 CAN Junction Connector

to Central Gateway ECU (Network Gateway ECU)

to Blind Spot Monitor Sensor LH

(w/ Blind Spot Monitor System)

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
Q63-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 13 CAN junction connector
Q63-2 (CANL) - K9-4 (CG)		200 Ω or higher	No. 13 CAN junction connector
Q64-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Central gateway ECU (network gateway ECU)
Q64-2 (CANL) - K9-4 (CG)		200 Ω or higher	Central gateway ECU (network gateway ECU)
Q65-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Blind spot monitor sensor LH*
Q65-2 (CANL) - K9-4 (CG)		200 Ω or higher	Blind spot monitor sensor LH*

*: w/ Blind Spot Monitor System

Result

Result	Proceed to
OK	A
NG (Line to central gateway ECU (network gateway ECU))	B
NG (Line to No. 13 CAN junction connector)	C
NG (Line to ECU or sensor)	D

REPLACE NO. 9 CAN JUNCTION CONNECTOR

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 13 CAN JUNCTION CONNECTOR)

GO TO STEP 15 Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

Disconnect the K146 central gateway ECU (network gateway ECU) connector.

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
K146-15 (CA5H) - K146-10 (GND)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
K146-16 (CA5L) - K146-10 (GND)		200 Ω or higher

Result

Result
OK
NG

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 9 CAN JUNCTION CONNECTOR)

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 10 CAN JUNCTION CONNECTOR)

Disconnect the Q68 No. 10 CAN junction connector.

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

DLC3

Front view of wire harness connector

(to No. 10 CAN Junction Connector)

to No. 13 CAN Junction Connector

to Central Gateway ECU (Network Gateway ECU)

to Blind Spot Monitor Sensor LH

(w/ Blind Spot Monitor System)

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
Q68-3 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 13 CAN junction connector
Q68-9 (CANL) - K9-4 (CG)		200 Ω or higher	No. 13 CAN junction connector
Q68-4 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Central gateway ECU (network gateway ECU)
Q68-10 (CANL) - K9-4 (CG)		200 Ω or higher	Central gateway ECU (network gateway ECU)
Q68-5 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Blind spot monitor sensor LH*
Q68-11 (CANL) - K9-4 (CG)		200 Ω or higher	Blind spot monitor sensor LH*

*: w/ Blind Spot Monitor System

Result

Result	Proceed to
OK	A
NG (Line to central gateway ECU (network gateway ECU))	B
NG (Line to No. 13 CAN junction connector)	C
NG (Line to ECU or sensor)	D

REPLACE NO. 10 CAN JUNCTION CONNECTOR

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 10 CAN JUNCTION CONNECTOR - NO. 13 CAN JUNCTION CONNECTOR)

GO TO STEP 15 Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

Disconnect the K146 central gateway ECU (network gateway ECU) connector.

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
K146-15 (CA5H) - K146-10 (GND)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
K146-16 (CA5L) - K146-10 (GND)		200 Ω or higher

Result

Result
OK
NG

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 10 CAN JUNCTION CONNECTOR)

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 12 CAN JUNCTION CONNECTOR)

Disconnect the K147, K148 and K149 No. 12 CAN junction connectors.

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

DLC3

Rear view of wire harness connector

(to No. 12 CAN Junction Connector)

to Hybrid Vehicle Control ECU Assembly

to No. 13 CAN Junction Connector

to Absorber Control ECU

(w/ AVS System)

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
K147-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Hybrid vehicle control ECU assembly
K147-2 (CANL) - K9-4 (CG)		200 Ω or higher	Hybrid vehicle control ECU assembly
K148-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 13 CAN junction connector
K148-2 (CANL) - K9-4 (CG)		200 Ω or higher	No. 13 CAN junction connector
K149-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Absorber control ECU*
K149-2 (CANL) - K9-4 (CG)		200 Ω or higher	Absorber control ECU*

*: w/ AVS System

Result

Result	Proceed to
OK	A
NG (Line to No. 13 CAN junction connector)	B
NG (Line to ECU or sensor)	C

REPLACE NO. 12 CAN JUNCTION CONNECTOR

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 12 CAN JUNCTION CONNECTOR - NO. 13 CAN JUNCTION CONNECTOR)

GO TO STEP 15 Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 13 CAN JUNCTION CONNECTOR)

Disconnect the cable from the negative (-) auxiliary battery terminal.
Disconnect the K151, K152, K153, K154 and K155 No. 13 CAN junction connectors.

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

*1	DLC3	-	-
*a	Rear view of wire harness connector (to No. 13 CAN Junction Connector)	*b	to No. 12 CAN Junction Connector
*c	to Forward Recognition Camera (w/ Lexus Safety System +)	*d	to Millimeter Wave Radar Sensor Assembly (w/ Lexus Safety System +)
*e	to Clearance Warning ECU Assembly (w/ LEXUS Parking Assist-sensor System)	*f	to No. 9 CAN Junction Connector or No. 10 CAN Junction Connector

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
K151-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 12 CAN junction connector
K151-2 (CANL) - K9-4 (CG)		200 Ω or higher	No. 12 CAN junction connector
K152-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Forward recognition camera*1
K152-2 (CANL) - K9-4 (CG)		200 Ω or higher	Forward recognition camera*1
K153-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Millimeter wave radar sensor assembly*1
K153-2 (CANL) - K9-4 (CG)		200 Ω or higher	Millimeter wave radar sensor assembly*1
K154-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Clearance warning ECU assembly*2
K154-2 (CANL) - K9-4 (CG)		200 Ω or higher	Clearance warning ECU assembly*2
K155-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 9 CAN junction connector or No. 10 CAN junction connector
K155-2 (CANL) - K9-4 (CG)		200 Ω or higher

*1: w/ Lexus Safety System +
*2: w/ LEXUS Parking Assist-sensor System

Result

Result	Proceed to
OK	A
NG (Line to No. 9 CAN junction connector or No. 10 CAN junction connector)	B
NG (Line to No. 12 CAN junction connector)	C
NG (Line to ECU or sensor)	D

REPLACE NO. 13 CAN JUNCTION CONNECTOR

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 12 CAN JUNCTION CONNECTOR) Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (ECU OR SENSOR) Click here

CHECK VEHICLE TYPE

Check whether the No. 9 CAN junction connector or No. 10 CAN junction connector is installed to the vehicle.

Click here

Component with harness connected

(No. 9 CAN Junction Connector)

Front view of wire harness connector

(to No. 10 CAN Junction Connector)

Result

Result	Proceed to
w/ No. 9 CAN Junction Connector	A
w/ No. 10 CAN Junction Connector	B

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 10 CAN JUNCTION CONNECTOR) Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 9 CAN JUNCTION CONNECTOR)

Disconnect the Q63, Q64 and Q65 No. 9 CAN junction connectors.

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

DLC3

Rear view of wire harness connector

(to No. 9 CAN Junction Connector)

to No. 13 CAN Junction Connector

to Hybrid Vehicle Control ECU Assembly

to Blind Spot Monitor Sensor LH

(w/ Blind Spot Monitor System)

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
Q63-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 13 CAN junction connector
Q63-2 (CANL) - K9-4 (CG)		200 Ω or higher	No. 13 CAN junction connector
Q64-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Hybrid vehicle control ECU assembly
Q64-2 (CANL) - K9-4 (CG)		200 Ω or higher	Hybrid vehicle control ECU assembly
Q65-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Blind spot monitor sensor LH*
Q65-2 (CANL) - K9-4 (CG)		200 Ω or higher	Blind spot monitor sensor LH*

*: w/ Blind Spot Monitor System

Result

Result	Proceed to
OK	A
NG (Line to No. 13 CAN junction connector)	B
NG (Line to ECU or sensor)	C

REPLACE NO. 9 CAN JUNCTION CONNECTOR

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 13 CAN JUNCTION CONNECTOR)

GO TO STEP 15 Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 10 CAN JUNCTION CONNECTOR)

Disconnect the Q68 No. 10 CAN junction connector.

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

DLC3

Front view of wire harness connector

(to No. 10 CAN Junction Connector)

to No. 13 CAN Junction Connector

to Hybrid Vehicle Control ECU Assembly

to Blind Spot Monitor Sensor LH

(w/ Blind Spot Monitor System)

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
Q68-3 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 13 CAN junction connector
Q68-9 (CANL) - K9-4 (CG)		200 Ω or higher	No. 13 CAN junction connector
Q68-4 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Hybrid vehicle control ECU assembly
Q68-10 (CANL) - K9-4 (CG)		200 Ω or higher	Hybrid vehicle control ECU assembly
Q68-5 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Blind spot monitor sensor LH*
Q68-11 (CANL) - K9-4 (CG)		200 Ω or higher	Blind spot monitor sensor LH*

*: w/ Blind Spot Monitor System

Result

Result	Proceed to
OK	A
NG (Line to No. 13 CAN junction connector)	B
NG (Line to ECU or sensor)	C

REPLACE NO. 10 CAN JUNCTION CONNECTOR

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 10 CAN JUNCTION CONNECTOR - NO. 13 CAN JUNCTION CONNECTOR)

GO TO STEP 15 Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 12 CAN JUNCTION CONNECTOR)

Disconnect the K147, K148, K149 and K150 No. 12 CAN junction connectors.

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

*1	DLC3	-	-
*a	Rear view of wire harness connector (to No. 12 CAN Junction Connector)	*b	to Central Gateway ECU (Network Gateway ECU)
*c	to No. 13 CAN Junction Connector	*d	to Absorber Control ECU (w/ AVS System)
*e	to Driving Support ECU Assembly (w/ Lexus Safety System +)	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
K147-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Central gateway ECU (network gateway ECU)
K147-2 (CANL) - K9-4 (CG)		200 Ω or higher	Central gateway ECU (network gateway ECU)
K148-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 13 CAN junction connector
K148-2 (CANL) - K9-4 (CG)		200 Ω or higher	No. 13 CAN junction connector
K149-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Absorber control ECU*1
K149-2 (CANL) - K9-4 (CG)		200 Ω or higher	Absorber control ECU*1
K150-1 (CANH) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Driving support ECU assembly*2
K150-2 (CANL) - K9-4 (CG)		200 Ω or higher	Driving support ECU assembly*2

*1: w/ AVS System
*2: w/ Lexus Safety System +

Result

Result	Proceed to
OK	A
NG (Line to central gateway ECU (network gateway ECU))	B
NG (Line to No. 13 CAN junction connector)	C
NG (Line to ECU or sensor)	D

REPLACE NO. 12 CAN JUNCTION CONNECTOR

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 12 CAN JUNCTION CONNECTOR - NO. 13 CAN JUNCTION CONNECTOR)

GO TO STEP 15 Click here

CHECK FOR SHORT TO GND IN CAN BUS LINE (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

Disconnect the K146 central gateway ECU (network gateway ECU) connector.

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
K146-15 (CA5H) - K146-10 (GND)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
K146-16 (CA5L) - K146-10 (GND)		200 Ω or higher

Result

Result
OK
NG

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 12 CAN JUNCTION CONNECTOR)

CHECK FOR SHORT TO GND IN CAN BUS LINE (ECU OR SENSOR)

Reconnect all wire harness connectors.
Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to GND is connected.

Click here

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

DLC3

Component with harness connected

(Central Gateway ECU (Network Gateway ECU))

Standard Resistance

Tester Connection	Condition	Specified Condition
K146-15 (CA5H) - K9-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
K146-16 (CA5L) - K9-4 (CG)		200 Ω or higher

Tech Tips

If the resistance changes to 200 Ω or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.
If the resistance does not become normal when the connector is disconnected from the ECU or sensor, check for a short to ground in the wire harness and repair or replace the wire harness or connector if necessary.

Result

Result
OK
NG

REPLACE ECU OR SENSOR

REPAIR OR REPLACE HARNESS OR CONNECTOR