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.

HINT
The diagnosis procedure is for when DTC U1002 is output by the power management control ECU (Techstream display: Power Management1).

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

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

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

Standard Resistance:

Result:

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

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

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

2. CHECK DTC OUTPUT

(a) Clear the DTC.

(b) Turn the power switch off.

(c) Turn the power switch on (IG), recheck the DTC.

Result:

B -- GO TO CIRCUITS INDICATED BY OUTPUT DTCS

A -- REPLACE POWER MANAGEMENT CONTROL ECU

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

(a) Disconnect the power management control ECU connector.

Text in Illustration

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

Standard Resistance:

NG -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (HYBRID VEHICLE CONTROL ECU)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU

4. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (HYBRID VEHICLE CONTROL ECU)

(a) Reconnect the power management control ECU connector.

(b) Disconnect the hybrid vehicle control ECU connector.

Text in Illustration

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

OK -- REPLACE HYBRID VEHICLE CONTROL ECU

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

(a) Reconnect the hybrid vehicle control ECU connector.

(b) Disconnect the wire harness connector form the CAN No. 2 junction connector upper side.

Text in Illustration

NG -- CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN J/C RH - CAN NO. 2 J/C)
OK -- Continue to next step.

6. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 2 J/C - POWER MANAGEMENT CONTROL ECU)

(a) Reconnect the wire harness connector to the CAN No. 2 junction connector upper side.

(b) Disconnect the wire harness connector form the CAN No. 2 junction connector lower side.

Text in Illustration

NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 J/C - POWER MANAGEMENT CONTROL ECU)

OK -- REPLACE CAN NO. 2 JUNCTION CONNECTOR

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

(a) Reconnect the wire harness connector to the CAN No. 2 junction connector lower side.

(b) Disconnect the instrument panel wire connector form the CAN junction connector RH.

Text in Illustration

NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN J/C RH - CAN NO. 2 J/C)
OK -- Continue to next step.

8. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN J/C RH - HYBRID VEHICLE CONTROL ECU)

(a) Reconnect the instrument panel wire connector to the CAN junction connector RH.

(b) Disconnect the engine room main wire connector form the CAN junction connector RH.

Text in Illustration

NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN J/C RH - HYBRID VEHICLE ECU)

OK -- REPLACE CAN JUNCTION CONNECTOR RH

9. CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (POWER MANAGEMENT CONTROL ECU)

(a) Disconnect the power management control ECU connector.

Text in Illustration

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

Standard Resistance:

NG -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (HYBRID VEHICLE CONTROL ECU)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU

10. CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (HYBRID VEHICLE CONTROL ECU)

(a) Reconnect the power management control ECU connector.

(b) Disconnect the hybrid vehicle control ECU connector.

Text in Illustration

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

OK -- REPLACE HYBRID VEHICLE CONTROL ECU

11. CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (CAN NO. 2 J/C - CAN J/C RH)

(a) Reconnect the hybrid vehicle control ECU connector.

(b) Disconnect the wire harness connector form the CAN No. 2 junction connector upper side.

Text in Illustration

NG -- CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (CAN J/C RH - CAN NO. 2 J/C)
OK -- Continue to next step.

12. CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (STEERING ANGLE SENSOR)

(a) Disconnect the spiral cable with sensor (steering angle sensor) 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 (STEERING ANGLE SENSOR)
OK -- Continue to next step.

13. CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (YAW RATE SENSOR)

(a) Disconnect the yaw rate sensor 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 (YAW RATE SENSOR)
OK -- Continue to next step.

14. CHECK FOR SHORT IN CAN NO. 2 BUS WIRES (PARKING ASSIST ECU)

HINT
For vehicles without the wide view front 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 (PARKING ASSIST ECU)
OK -- Continue to next step.