U0114

NETWORKING: CAN COMMUNICATION SYSTEM: U1002 (CAN No. 2 BUS),U0114: Lost Communication with Gateway Module (Network Gateway ECU)

DTC U1002 (CAN No. 2 BUS) - Lost Communication with Gateway Module (Network Gateway ECU)

DTC U0114 - Lost Communication with 4WD Control ECU

DESCRIPTION

- The network gateway ECU will store this DTC when no signals can be received from the ECUs that have been memorized as those that are connected to the CAN No. 2 bus.
- When the network gateway ECU receives a response signal from the ECUs connected to the CAN No. 2 bus, the network gateway ECU recognizes and memorizes that the ECU is connected to the CAN No. 2 bus. Based on this memorized data, the network gateway ECU monitors for malfunctions in the ECUs connected to the CAN No. 2 bus when communicating with those ECUs. If the network gateway ECU cannot receive response signals from the ECUs that have been memorized as those connected to the CAN No. 2 bus, the network gateway ECU determines that a malfunction exists.

WIRING DIAGRAM

INSPECTION PROCEDURE
NOTICE:
- Turn the ignition switch off before measuring the resistance of CAN bus main wires and the CAN bus branch wires.
- After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
- Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If any doors need to be opened in order to check the connectors, open the doors and leave them open.
HINT:
- Operating the ignition switch, any switches or a door triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.
- 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 will help determine the cause of the malfunction.

PROCEDURE

1. CHECK CAN NO. 2 BUS WIRE
(a) Turn the ignition switch off.

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

Result:

C -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE
B -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (NETWORK GATEWAY ECU - CAN NO. 3 JUNCTION CONNECTOR)
A -- Continue to next step.

2. CHECK OPEN IN CAN BUS WIRE (4WD CONTROL ECU)
(a) Turn the ignition switch off.
(b) Disconnect the 4WD control ECU connector.

NG -- REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (4WD CONTROL ECU BRANCH WIRE)
OK -- Continue to next step.

3. CHECK WIRE HARNESS (4WD CONTROL ECU - BATTERY AND BODY GROUND)
(a) Disconnect the 4WD control ECU connector.

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (4WD CONTROL ECU POWER SOURCE CIRCUIT)
OK -- Continue to next step.

4. CONNECT
(a) Reconnect the 4WD control ECU connector.
NEXT -- Continue to next step.

5. CLEAR DTC
(a) Clear the DTC.
NEXT -- Continue to next step.

6. RECONFIRM DTC OUTPUT
(a) Check the DTC.
Result:

B -- REPLACE NETWORK GATEWAY ECU
A -- CHECK CONNECTOR CONNECTION CONDITION
7. REPLACE NETWORK GATEWAY ECU Removal
(a) Replace the network gateway ECU.
NEXT -- Continue to next step.

8. RECONFIRM DTC OUTPUT
(a) Check the DTC.
Result:

B -- REPLACE 4WD ECU ASSEMBLY
A -- END
9. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (NETWORK GATEWAY ECU - CAN NO. 3 JUNCTION CONNECTOR)
(a) Disconnect the network gateway ECU connector.

(b) Measure the resistance of the wire harness side connectors.
Standard Resistance:

NG -- CONNECT
OK -- REPLACE NETWORK GATEWAY ECU
10. CONNECT
(a) Reconnect the network gateway ECU connector.
NEXT -- Continue to next step.

11. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 3 JUNCTION CONNECTOR - NETWORK GATEWAY ECU)
(a) Disconnect the CAN No. 3 junction connector (E68).

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 JUNCTION CONNECTOR - NETWORK GATEWAY MAIN WIRE)
OK -- REPAIR OR REPLACE INSTRUMENT PANEL WIRE (CAN NO. 3 JUNCTION CONNECTOR)
12. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE
(a) Disconnect the network gateway ECU connector.

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (4WD CONTROL ECU BRANCH WIRE)
OK -- REPLACE NETWORK GATEWAY ECU
13. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (4WD CONTROL ECU BRANCH WIRE)

(a) Disconnect the CAN No. 3 junction connector (E66).

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 JUNCTION CONNECTOR - NETWORK GATEWAY MAIN WIRE)
OK -- Continue to next step.

14. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (4WD CONTROL ECU BRANCH WIRE)
(a) Disconnect the 4WD control ECU connector.

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (4WD CONTROL ECU BRANCH WIRE)
OK -- REPLACE 4WD ECU ASSEMBLY
15. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 JUNCTION CONNECTOR - NETWORK GATEWAY MAIN WIRE)

(a) Disconnect the CAN No. 3 junction connector (E68).

(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- REPAIR OR REPLACE CAN NO. 2 BUS MAIN WIRE OR CONNECTOR (NETWORK GATEWAY ECU - CAN NO. 3 JUNCTION CONNECTOR)
OK -- REPAIR OR REPLACE INSTRUMENT PANEL WIRE (CAN NO. 3 JUNCTION CONNECTOR)