Up to 08/2009

NETWORKING: CAN COMMUNICATION SYSTEM: U1002: Lost Communication with Gateway Module (Power Management2)
U1002 - Lost Communication with Gateway Module (Power Management2)

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 power management bus.

* When the power management control ECU receives a response signal from the ECUs connected to the power management bus, the power management control ECU recognizes and memorizes that the ECU is connected to the power management bus. Based on this memorized data, the power management control ECU monitors for malfunctions in the ECUs connected to the power management 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 power management 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 POWER MANAGEMENT BUS WIRE

(a) Turn the power switch off.

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

Standard Resistance:

(c) Disconnect 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:

D -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (POWER MANAGEMENT CONTROL ECU)

C -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (POWER MANAGEMENT CONTROL ECU)

B -- CHECK FOR OPEN IN POWER MANAGEMENT BUS MAIN WIRE (POWER MANAGEMENT CONTROL ECU)

A -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

2. CHECK FOR OPEN IN POWER MANAGEMENT BUS MAIN 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 OPEN IN POWER MANAGEMENT BUS MAIN WIRE (ECM)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

3. CHECK FOR OPEN IN POWER MANAGEMENT BUS MAIN WIRE (ECM)

(a) Reconnect the power management control ECU connector.

(b) Disconnect the ECM connector.

Text in Illustration

NG -- CHECK FOR OPEN IN POWER MANAGEMENT BUS MAIN WIRE (CAN NO. 9 J/C MAIN WIRE)

OK -- REPLACE ECM Removal

4. CHECK FOR OPEN IN POWER MANAGEMENT BUS MAIN WIRE (CAN NO. 9 J/C MAIN WIRE)

(a) Reconnect the ECM connector.

(b) Disconnect the CAN No. 9 junction connector.

Text in Illustration

Result:

C -- REPAIR OR REPLACE POWER MANAGEMENT BUS MAIN WIRE OR CONNECTOR (CAN NO. 9 J/C - POWER MANAGEMENT CONTROL ECU)

B -- REPAIR OR REPLACE POWER MANAGEMENT BUS MAIN WIRE OR CONNECTOR (CAN NO. 9 J/C - ECM)

A -- REPLACE CAN NO. 9 JUNCTION CONNECTOR

5. CHECK FOR SHORT IN POWER MANAGEMENT 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 POWER MANAGEMENT BUS WIRE (ECM)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

6. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (ECM)

(a) Reconnect the power management control ECU connector.

(b) Disconnect the ECM connector.

Text in Illustration

NG -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C MAIN WIRE)

OK -- REPLACE ECM Removal

7. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C MAIN WIRE)

(a) Reconnect the ECM connector.

(b) Disconnect the CAN No. 9 junction connector.

Text in Illustration

Result:

C -- REPAIR OR REPLACE POWER MANAGEMENT BUS MAIN WIRE OR CONNECTOR (CAN NO. 9 J/C - POWER MANAGEMENT CONTROL ECU)

B -- REPAIR OR REPLACE POWER MANAGEMENT BUS MAIN WIRE OR CONNECTOR (CAN NO. 9 J/C - ECM)
A -- Continue to next step.

8. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C - AIR CONDITIONING AMPLIFIER)

(a) Disconnect the air conditioning amplifier connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE POWER MANAGEMENT BUS BRANCH WIRE OR CONNECTOR (CAN NO. 9 J/C - A/C ECU)
OK -- Continue to next step.

9. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C - SKID CONTROL ECU)

(a) Disconnect the skid 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 POWER MANAGEMENT BUS BRANCH WIRE OR CONNECTOR (CAN NO. 9 J/C - SKID CONTROL ECU)
OK -- Continue to next step.

10. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C)

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

Standard Resistance:

Text in Illustration

NG -- REPLACE CAN NO. 9 JUNCTION CONNECTOR
OK -- Continue to next step.

11. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (ECUS)

(a) Connect the probes of an ohmmeter to terminals F98-31 (CA3P) and F98-30 (CA3N) 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

12. CHECK FOR SHORT IN POWER MANAGEMENT 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

HINT
It is only necessary to perform the inspection in the above table for the result (open or short circuit) that was obtained in the Check CAN Bus Wire inspection.

Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check CAN Bus Wire inspection.

NG -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (ECM)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

13. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (ECM)

(a) Disconnect the ECM connectors.

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

Standard Resistance:

Text in Illustration

HINT
It is only necessary to perform the inspection in the above table for the result (open or short circuit) that was obtained in the Check CAN Bus Wire inspection.

Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check CAN Bus Wire inspection.

NG -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C MAIN WIRE)

OK -- REPLACE ECM Removal

14. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C MAIN WIRE)

(a) Disconnect the CAN No. 9 junction connector.

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

Standard Resistance:

Text in Illustration

E -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C - SKID CONTROL ECU)

D -- REPAIR OR REPLACE POWER MANAGEMENT BUS MAIN WIRE OR CONNECTOR (CAN NO. 9 J/C - ECM)

C -- REPAIR OR REPLACE POWER MANAGEMENT BUS MAIN WIRE OR CONNECTOR (CAN NO. 9 J/C - POWER MANAGEMENT CONTROL ECU)

B -- CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C - A/C ECU)

A -- REPLACE CAN NO. 9 JUNCTION CONNECTOR

15. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C - A/C ECU)

(a) Disconnect the air conditioning amplifier connector.

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

Standard Resistance:

Text in Illustration

HINT
It is only necessary to perform the inspection in the above table for the result (open or short circuit) that was obtained in the Check CAN Bus Wire inspection.

Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check CAN Bus Wire inspection.

NG -- REPAIR OR REPLACE POWER MANAGEMENT BUS BRANCH WIRE OR CONNECTOR (CAN NO. 9 J/C - A/C ECU)

OK -- REPLACE AIR CONDITIONING AMPLIFIER Removal

16. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 9 J/C - SKID CONTROL ECU)

(a) Disconnect the skid control ECU connector.

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

Standard Resistance:

Text in Illustration