DESCRIPTION
There may be a short circuit between one of the CAN bus wires and GND when no resistance exists between terminal 15 (CA5H) of the central gateway ECU and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU and terminal 4 (CG) of the DLC3.
| Detection Item | Trouble Area |
|---|---|
| No resistance exists between terminal 15 (CA5H) of the central gateway ECU and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU and terminal 4 (CG) of the DLC3. |
|
*1: w/ Pre-crash Safety System
*2: w/o Pre-crash Safety System
*3: w/ Blind Spot Monitor System
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 Click here.
Before measuring the resistance of the CAN bus, turn the engine 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 engine 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 Click here.
After the repair, perform CAN Bus Check and check that all the ECUs and sensors connected to the CAN communication system are displayed Click here.
Tech Tips
Operating the engine 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 GND IN CAN BUS WIRE (CENTRAL GATEWAY ECU - NO. 3 CAN JUNCTION CONNECTOR)
| *a | Front view of wire harness connector (to Central Gateway ECU) |
| *b | Front view of DLC3 |
Disconnect the cable from the negative (-) battery terminal.
Disconnect the central gateway ECU connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE CENTRAL GATEWAY ECU Click here |
| NG |
|
CONNECT CONNECTOR
Reconnect the E137 central gateway ECU connector.
| NEXT |
|
CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 CAN JUNCTION TERMINAL - NO. 4 CAN JUNCTION CONNECTOR)
| *a | Rear view of wire harness connector (to No. 1 CAN Junction Terminal) |
| *b | Front view of DLC3 |
Disconnect the No. 1 CAN junction terminal connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE NO. 1 CAN JUNCTION TERMINAL |
| NG |
|
CONNECT CONNECTOR
Reconnect the K57 No. 1 CAN junction terminal connector.
| NEXT |
|
CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 CAN JUNCTION CONNECTOR)
Disconnect the No. 3 CAN junction connector.
| *a | Front view of wire harness connector (to No. 3 CAN Junction Connector) |
*b | Front view of DLC3 |
| *c | to No. 4 CAN Junction Connector | *d | to Driving Support ECU Assembly (w/ Pre-crash Safety System) |
| *e | to Central Gateway ECU | *f | to Millimeter Wave Radar Sensor Assembly (w/ Pre-crash Safety System) |
| *g | to Clearance Warning ECU Assembly | *h | to Parking Assist ECU |
| *i |
|
- | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*1: w/ Pre-crash Safety System
*2: w/o Pre-crash Safety System
| Result | Proceed to |
|---|---|
| OK | A |
| NG (Central gateway ECU CAN main wire) | B |
| NG (No. 4 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wires) | D |
| A |
|
REPLACE NO. 3 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 3 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU) |
| D |
|
CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECU, SENSOR) Click here |
| C |
|
CONNECT CONNECTOR
Reconnect the E159 No. 3 CAN junction connector.
| NEXT |
|
CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 4 CAN JUNCTION CONNECTOR)
Disconnect the No. 4 CAN junction connectors.
| *1 | No. 4 CAN Junction Connector | - | - |
| *a | Rear view of wire harness connector (to No. 4 CAN Junction Connector) |
*b | Front view of DLC3 |
| Code | Color (CANH Side) | Color (CANL Side) | Connect to |
|---|---|---|---|
| K62 | W | B | No. 3 CAN Junction Connector |
| K63 | SB | B | No. 1 CAN Junction Terminal |
| K64 | LG | B | Parking Brake ECU Assembly |
| K65 | R | B | Blind Spot Monitor Sensor LH* |
| K66 | L | B | Suspension Control ECU |
*: w/ Blind Spot Monitor System
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*: w/ Blind Spot Monitor System
| Result | Proceed to |
|---|---|
| OK | A |
| NG (No. 3 CAN junction connector CAN main wire) | B |
| NG (No. 1 CAN junction terminal CAN main wire) | C |
| NG (ECU or sensor CAN branch wires) | D |
| A |
|
REPLACE NO. 4 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION CONNECTOR) |
| C |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 1 CAN JUNCTION TERMINAL) |
| D |
|
CHECK FOR SHORT TO GND 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 GND is connected.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
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.
| OK |
|
REPLACE CORRESPONDING ECU OR SENSOR |
| NG |
|
REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRES OR CONNECTOR |