DESCRIPTION
There may be an open circuit in one of the CAN main bus wire and/or a central gateway ECU (network gateway ECU) branch wire when the resistance between terminals 18 (CA4H) and 17 (CA4L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.
Symptom | Trouble Area |
---|---|
Resistance between terminals 18 (CA4H) and 17 (CA4L) of central gateway ECU (network gateway ECU) is 70 Ω or higher. |
|
This malfunction is not related to the lines of a CAN branch except the central gateway ECU (network gateway ECU) branch wire or to ECUs or sensors connected to a CAN branch.
WIRING DIAGRAM
*a | Combination Meter Assembly |
*b | Central Gateway ECU (Network Gateway ECU) |
*c | No. 1 CAN Junction Connector |
*d | No. 2 CAN Junction Connector |
CAUTION / NOTICE / HINT
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
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.
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 or any 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 negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.
Some parts must be initialized and set when replacing or removing and installing parts.
After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
DTC check procedure: Turn the engine switch on (IG) and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes 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.
When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored
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 OPEN IN CAN BUS WIRE (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 1 CAN JUNCTION CONNECTOR)
Disconnect the cable from the negative (-) battery terminal.
*a | Front view of wire harness connector (to Central Gateway ECU [Network Gateway ECU]) |
Disconnect the central gateway ECU (network gateway ECU) connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||
---|---|---|---|---|---|---|
|
Result | |||
---|---|---|---|
|
NG |
REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 1 CAN JUNCTION CONNECTOR) |
OK |
CONNECT CONNECTOR
Connect the I164 central gateway ECU (network gateway ECU) connector.
Result | ||
---|---|---|
|
Next |
CHECK FOR OPEN IN CAN BUS WIRE (NO. 1 CAN JUNCTION CONNECTOR)
*a | Front view of wire harness connector (to No. 1 CAN Junction Connector) |
*b | to No. 2 CAN Junction Connector |
*c | to Combination Meter Assembly |
Disconnect the No. 1 CAN junction connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Result | ||||||||
---|---|---|---|---|---|---|---|---|
|
A |
REPLACE NO. 1 CAN JUNCTION CONNECTOR |
C |
CONNECT CONNECTOR Click here |
B |
CONNECT CONNECTOR
Connect the I93 No. 1 CAN junction connector.
Result | ||
---|---|---|
|
Next |
CHECK FOR OPEN IN CAN BUS WIRE (COMBINATION METER ASSEMBLY - NO. 1 CAN JUNCTION CONNECTOR)
*a | Front view of wire harness connector (to Combination Meter Assembly) |
Disconnect the combination meter assembly connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||
---|---|---|---|---|---|---|
|
Result | |||
---|---|---|---|
|
OK |
REPLACE COMBINATION METER ASSEMBLY Click here |
NG |
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (COMBINATION METER ASSEMBLY - NO. 1 CAN JUNCTION CONNECTOR) |
CONNECT CONNECTOR
Connect the I93 No. 1 CAN junction connector.
Result | ||
---|---|---|
|
Next |
CHECK FOR OPEN IN CAN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR)
*a | Front view of wire harness connector (to No. 2 CAN Junction Connector) |
*b | to No. 1 CAN Junction Connector |
*c | to ECM |
Disconnect the No. 2 CAN junction connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Result | ||||||||
---|---|---|---|---|---|---|---|---|
|
A |
REPLACE NO. 2 CAN JUNCTION CONNECTOR |
B |
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 1 CAN JUNCTION CONNECTOR) |
C |
CONNECT CONNECTOR
Connect the I94 No. 2 CAN junction connector.
Result | ||
---|---|---|
|
Next |
CHECK FOR OPEN IN CAN BUS WIRE (ECM - NO. 2 CAN JUNCTION CONNECTOR)
*a | Front view of wire harness connector (to ECM) |
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||
---|---|---|---|---|---|---|
|
Result | |||
---|---|---|---|
|
OK |
REPLACE ECM for 8AR-FTS: Click here |
NG |
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (ECM - NO. 2 CAN JUNCTION CONNECTOR) |