Part 1

NETWORKING: CAN COMMUNICATION SYSTEM: U1002: Lost Communication with Gateway Module (Power Management1)
U1002 - Lost Communication with Gateway Module (Power Management1)

DESCRIPTION

* The power management control 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 power management control ECU receives a response signal from the ECUs connected to the CAN No. 2 bus, the power management control ECU recognizes and memorizes that the ECU is connected to the CAN No. 2 bus. Based on this memorized data, the power management control ECU monitors for malfunctions in the ECUs connected to the CAN No. 2 bus when communicating with those ECUs. If the power management control ECU cannot receive response signals from the ECUs that have been memorized as those connected to the CAN No. 2 bus, the power management control ECU determines that a malfunction exists.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
* Turn the power switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
* Turn the power switch off before inspecting CAN bus wires for a ground short.
* After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
* Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.
HINT
* Operating the power switch, any other switches or a door triggers related ECU and sensor communication on 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 may help determine the cause of the malfunction.
PROCEDURE

1. CHECK CAN NO. 2 BUS WIRE

(a) Turn the power switch off.

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

Standard Resistance:

Text in Illustration

Result:

C -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (POWER MANAGEMENT CONTROL ECU)

B -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (POWER MANAGEMENT CONTROL ECU MAIN WIRE)
A -- Continue to next step.

2. CHECK CAN NO. 2 BUS WIRE

(a) Turn the power switch off.

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

Standard Resistance:

(c) Disconnected the cable from the negative (-) battery terminal.

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

Standard Resistance:

Text in Illustration

Result:

B -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (POWER MANAGEMENT CONTROL ECU)

A -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

3. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (POWER MANAGEMENT CONTROL ECU MAIN WIRE)

(a) Disconnect the power management control ECU connector.

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

Standard Resistance:

Text in Illustration

NG -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 3 J/C)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

4. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 3 J/C)

(a) Reconnect the power management control ECU connector.

(b) Disconnect the CAN No. 3 junction connector.

Text in Illustration

Result:

C -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - POWER MANAGEMENT CONTROL ECU)

B -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 4 J/C)

A -- REPLACE CAN NO. 3 JUNCTION CONNECTOR

5. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 4 J/C)

(a) Reconnect the CAN No. 3 junction connector.

(b) Disconnect the CAN No. 4 junction connector.

Text in Illustration

Result:

C -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 5 J/C)

B -- REPAIR OR REPLACE CAN NO. 2 BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - CAN NO. 4 J/C)

A -- REPLACE CAN NO. 4 JUNCTION CONNECTOR

6. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 5 J/C)

HINT
- The connectors connected to the CAN junction connectors can be distinguished according to the color of the communication bus wires.

- Reconnecting the connectors to non-specified positions on the CAN junction connectors does not affect system operation. However, it is preferred to reconnect the connectors to their original positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.

(a) Reconnect the CAN No. 4 junction connector.

(b) Disconnect the CAN bus main wire connector from the CAN No. 5 junction connector.

Text in Illustration

NG -- REPAIR OR REPLACE CAN NO. 2 BUS MAIN WIRE OR CONNECTOR (CAN NO. 4 J/C - CAN NO. 5 J/C)

OK -- REPLACE CAN NO. 5 JUNCTION CONNECTOR

7. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (POWER MANAGEMENT CONTROL ECU)

(a) Disconnect the power management control ECU connector.

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

Standard Resistance:

Text in Illustration

NG -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

8. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C)

(a) Reconnect the power management control ECU connector.

(b) Disconnect the CAN No. 3 junction connector.

Text in Illustration

Result:

C -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - POWER MANAGEMENT CONTROL ECU)

B -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 4 J/C)
A -- Continue to next step.

9. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C - SUSPENSION CONTROL ECU)

HINT
For vehicles without the air suspension, go to the next step.

(a) Disconnect the suspension control ECU connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (CAN NO. 3 J/C - SUSPENSION CONTROL ECU)
OK -- Continue to next step.

10. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C - SEAT BELT CONTROL ECU)

HINT
For vehicles without the pre-collision system, go to the next step.

(a) Disconnect the seat belt control ECU connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (CAN NO. 3 J/C - SEAT BELT CONTROL ECU)
OK -- Continue to next step.

11. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C - PARKING ASSIST ECU)

HINT
For vehicles without the side monitor system, go to the next step.

(a) Disconnect the parking assist ECU connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (CAN NO. 3 J/C - PARKING ASSIST ECU)
OK -- Continue to next step.

12. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C - CLEARANCE WARNING ECU)

HINT
For vehicles with the side monitor system, go to the next step.

(a) Disconnect the clearance warning ECU connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (CAN NO. 3 J/C - CLEARANCE WARNING ECU)
OK -- Continue to next step.

13. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 J/C)

(a) Reconnect the CAN No. 3 junction connector.

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

Standard Resistance:

Text in Illustration

NOTICE:
The resistance must be measured after the main wire connected ECU and junction connector are reconnected.

NG -- REPLACE CAN NO. 3 JUNCTION CONNECTOR
OK -- Continue to next step.

14. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (ECUS)

(a) Connect the probes of an ohmmeter to terminals F97-34 (CA2H) and F97-35 (CA2L) of the power management control ECU.

Text in Illustration

(b) While observing the resistance value shown on the tester, reconnect the each ECU connector until the resistance becomes abnormal (Below 54 Ohms).

(c) Replace the ECU that caused the total resistance to drop below 54 Ohms when it was reconnected.

HINT
If the resistance becomes abnormal when an ECU connector is reconnected, there may be a short in the ECU.

NEXT -- REPLACE CORRESPONDING ECU

15. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 4 J/C)

(a) Reconnect the CAN No. 3 junction connector.

(b) Disconnect the CAN No. 4 junction connector.

Text in Illustration

Result:

C -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN J/C NO. 5)

B -- REPAIR OR REPLACE CAN NO. 2 BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - CAN NO. 4 J/C)
A -- Continue to next step.