Networking. Dtc U1002 Lost Communication With Gateway Module (Power Management2)

The power management control ECU stores this DTC when no signals can be received from the ECUs that have been memorized as those 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.
If 2 or more DTCs are output during the DTC check, one side of the CAN branch wire may be open (one side of the CANH [branch wire]/CANL [branch wire] of the ECU and/or sensor is open).

DTC Code	DTC Detection Condition	Trouble Area
U1002	Lost communication with the gateway module (Power Management2).	Power management bus circuit Air conditioning amplifier assembly CAN branch wire or connector Power management control ECU CAN main wire or connector ECM CAN main wire or connector Air conditioning amplifier assembly Power management control ECU ECM No. 3 junction connector

WIRING DIAGRAM

Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Networking.Lin Communication System.
Dtc
U1002 Lost Communication With Gateway Module (Power Management2)

INSPECTION PROCEDURE

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:

Operating the engine switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

1.DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the airbag system.
NOTICE:
1. After turning the engine switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work (LandCruiser RM000003YMD00TX.html).
2. When disconnecting the cable, some systems need to be initialized after the cable is reconnected (LandCruiser RM000003YMF011X.html).

NEXT

2.CHECK CAN BUS WIRE (CHECK CAN MAIN WIRE FOR DISCONNECTION, CHECK BUS LINE FOR SHORT)

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition	Resistance: Malfunction
G51-12 (CA3P) - G51-11 (CA3N)	Engine switch off	54 to 69 Ω	Below 53 Ω: Short in line
G51-12 (CA3P) - G51-11 (CA3N)	Engine switch off	54 to 69 Ω	Higher than 70 Ω: Open in CAN main bus line
G51-12 (CA3P) - G51-1 (AM22)	Engine switch off	6 kΩ or higher	Below 6 kΩ: +B short
G51-11 (CA3N) - G51-1 (AM22)	Engine switch off	6 kΩ or higher	Below 6 kΩ: +B short
G51-12 (CA3P) - G51-6 (GND)	Engine switch off	200 Ω or higher	Below 200 Ω: Ground short
G51-11 (CA3N) - G51-6 (GND)	Engine switch off	200 Ω or higher	Below 200 Ω: Ground short

Text in Illustration
*a	Component with harness connected (Power Management Control ECU)

Result
Result	Proceed to
NG Open in CAN main bus line	A
NG Short in line +B short Ground short	B
OK	C

Go to step 9

Go to step 18

A

3.CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 3 JUNCTION CONNECTOR - ECM)

Disconnect the G98 No. 3 junction connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
G98-9 (CANH) - G98-20 (CANL)
Engine switch off
108 to 132 Ω
Text in Illustration
*a
Rear view of wire harness connector
(to No. 3 Junction Connector)

Go to step 5

OK

4.CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 3 JUNCTION CONNECTOR - POWER MANAGEMENT CONTROL ECU)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
G98-11 (CANH) - G98-22 (CANL)
Engine switch off
108 to 132 Ω
Text in Illustration
*a
Rear view of wire harness connector
(to No. 3 Junction Connector)

Go to step 7

REPLACE NO. 3 JUNCTION CONNECTOR

5.CONNECT CONNECTOR

Reconnect the G98 No. 3 junction connector.

NEXT

6.CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - NO. 3 JUNCTION CONNECTOR)

Disconnect the ECM connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
G57-20 (CANP) - G57-21 (CANN)
Engine switch off
108 to 132 Ω
Text in Illustration
*a
Front view of wire harness connector
(to ECM)

REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (ECM - NO. 3 JUNCTION CONNECTOR)

REPLACE ECM (LandCruiser RM0000013Z002CX.html)

7.CONNECT CONNECTOR

Reconnect the G98 No. 3 junction connector.

NEXT

8.CHECK FOR OPEN IN CAN BUS MAIN WIRE (POWER MANAGEMENT CONTROL ECU - NO. 3 JUNCTION CONNECTOR)

Disconnect the power management control ECU connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
G51-12 (CA3P) - G51-11 (CA3N)
Engine switch off
108 to 132 Ω
Text in Illustration
*a
Rear view of wire harness connector
(to Power Management Control ECU)

REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO POWER MANAGEMENT CONTROL ECU (POWER MANAGEMENT CONTROL ECU - NO. 3 JUNCTION CONNECTOR)

REPLACE POWER MANAGEMENT CONTROL ECU (LandCruiser RM0000039R5026X.html)

9.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)

Disconnect the G98 No. 3 junction connector.

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
G98-10 (CANH) - G98-21 (CANL)	Engine switch off	200 Ω or higher
G98-10 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
G98-21 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
G98-10 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
G98-21 (CANL) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

Text in Illustration
*a	Rear view of wire harness connector (to No. 3 Junction Connector)
*b	Front view of DLC3

Go to step 12

OK

10.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - ECM)

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
G98-9 (CANH) - G98-20 (CANL)	Engine switch off	108 to 132 Ω
G98-9 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
G98-20 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
G98-9 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
G98-20 (CANL) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

Text in Illustration
*a	Rear view of wire harness connector (to No. 3 Junction Connector)
*b	Front view of DLC3

Go to step 14

OK

11.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - POWER MANAGEMENT CONTROL ECU)

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
G98-11 (CANH) - G98-22 (CANL)	Engine switch off	108 to 132 Ω
G98-11 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
G98-22 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
G98-11 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
G98-22 (CANL) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

Text in Illustration
*a	Rear view of wire harness connector (to No. 3 Junction Connector)
*b	Front view of DLC3

Go to step 16

REPLACE NO. 3 JUNCTION CONNECTOR

12.CONNECT CONNECTOR

Reconnect the G98 No. 3 junction connector.

NEXT

13.CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER ASSEMBLY)

Disconnect the air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
G25-11 (CANH) - G25-12 (CANL)	Engine switch off	54 to 69 Ω
G25-11 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
G25-12 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
G25-11 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
G25-12 (CANL) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

Text in Illustration
*a	Front view of wire harness connector (to Air Conditioning Amplifier Assembly)
*b	Front view of DLC3

REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO AIR CONDITIONING AMPLIFIER ASSEMBLY (CANH, CANL)

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (LandCruiser RM0000039R5028X.html)

14.CONNECT CONNECTOR

Reconnect the G98 No. 3 junction connector.

NEXT

15.CHECK FOR SHORT IN CAN BUS WIRES (ECM)

Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
G57-20 (CANP) - G57-21 (CANN)	Engine switch off	108 to 132 Ω
G57-20 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
G57-21 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
G57-20 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
G57-21 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

Text in Illustration
*a	Front view of wire harness connector (to ECM)
*b	Front view of DLC3

REPAIR OR REPLACE ECM MAIN WIRE OR CONNECTOR (CANP, CANN)

REPLACE ECM (LandCruiser RM0000013Z002CX.html)

16.CONNECT CONNECTOR

Reconnect the G98 No. 3 junction connector.

NEXT

17.CHECK FOR SHORT IN CAN BUS WIRES (POWER MANAGEMENT CONTROL ECU)

Disconnect the power management control ECU connector.

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
G51-12 (CA3P) - G51-11 (CA3N)	Engine switch off	108 to 132 Ω
G51-12 (CA3P) - G48-4 (CG)	Engine switch off	200 Ω or higher
G51-11 (CA3N) - G48-4 (CG)	Engine switch off	200 Ω or higher
G51-12 (CA3P) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
G51-11 (CA3N) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

Text in Illustration
*a	Rear view of wire harness connector (to Power Management Control ECU)
*b	Front view of DLC3

REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO POWER MANAGEMENT CONTROL ECU (CA3P, CA3N)

REPLACE POWER MANAGEMENT CONTROL ECU (LandCruiser RM0000039R5026X.html)

18.CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY AND GROUND)

Connect the cable to the negative (-) battery terminal.
NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected (LandCruiser RM000003YMF011X.html).

Disconnect the power management control ECU connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Condition
Specified Condition
G51-5 (GND2) - Body ground
Always
Below 1 Ω
G51-6 (GND) - Body ground
Always
Below 1 Ω

Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
Condition
Specified Condition
G51-1 (AM22) - Body ground
Always
11 to 14 V
G51-2 (AM21) - Body ground
Always
11 to 14 V

Text in Illustration
*a	Rear view of wire harness connector (to Power Management Control ECU)

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE POWER MANAGEMENT CONTROL ECU (LandCruiser RM0000039R5026X.html)

Tester Connection	Condition	Specified Condition
G51-5 (GND2) - Body ground	Always	Below 1 Ω
G51-6 (GND) - Body ground	Always	Below 1 Ω