Dtc U1002 Lost Communication With Gateway Module (Ms Bus)

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

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

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

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

CONNECT CONNECTOR

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

CONNECT CONNECTOR

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

CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - FRONT POWER SEAT SWITCH LH)

CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - MULTIPLEX TILT AND TELESCOPIC ECU)

CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - DRIVING SUPPORT SWITCH CONTROL ECU)

CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - MAIN BODY ECU)

CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - NO. 8 JUNCTION CONNECTOR)

CONNECT CONNECTOR

CHECK FOR SHORT IN CAN BUS WIRES (FRONT POWER SEAT SWITCH LH)

CONNECT CONNECTOR

CHECK FOR SHORT IN CAN BUS WIRES (MULTIPLEX TILT AND TELESCOPIC ECU)

CONNECT CONNECTOR

CHECK FOR SHORT IN CAN BUS WIRES (DRIVING SUPPORT SWITCH CONTROL ECU)

CONNECT CONNECTOR

CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)

CONNECT CONNECTOR

CHECK FOR SHORT IN CAN BUS WIRES (NO. 8 JUNCTION CONNECTOR)

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND)

DTC U1002 Lost Communication with Gateway Module (MS Bus)

DESCRIPTION

1. The main body ECU (multiplex network body ECU) stores this DTC when no signals can be received from the ECUs that have been memorized as those connected to the CAN MS bus.
   
2. When the main body ECU (multiplex network body ECU) receives a response signal from the ECUs connected to the CAN MS bus, the main body ECU (multiplex network body ECU) recognizes and memorizes that the ECU is connected to the CAN MS bus. Based on this memorized data, the main body ECU (multiplex network body ECU) monitors for malfunctions in the ECUs connected to the CAN MS bus when communicating with those ECUs. If the main body ECU (multiplex network body ECU) cannot receive response signals from the ECUs that have been memorized as those connected to the CAN MS bus, the main body ECU (multiplex network body ECU) determines that a malfunction exists.
   
3. 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 [CAN branch wire]/CANL [CAN branch wire] of the ECU and/or sensor is open).
   

DTC Code	DTC Detection Condition	Trouble Area
U1002 (CAN MS BUS)	Lost communication with the gateway module (MS bus).	MS bus circuit Main body ECU (multiplex network body ECU) CAN main wire or connector Front power seat switch LH CAN branch wire or connector*1 Multiplex tilt and telescopic ECU CAN branch wire or connector*2 Driving support switch control ECU CAN branch wire or connector*3 Main body ECU (multiplex network body ECU) Front power seat switch LH*1 Multiplex tilt and telescopic ECU*2 Driving monitor switch control ECU*3 No. 3 junction connector No. 8 junction connector

1. *1: w/ Seat Position Memory
   
2. *2: for Power Tilt and Power Telescopic Steering Column
   
3. *3: w/ Multi-function Switch
   

WIRING DIAGRAM

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

1. 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 (CAN MAIN WIRE FOR DISCONNECTION, BUS LINE FOR SHORT CIRCUIT)

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition	Resistance: Malfunction
   G103-3 (CANP) - G103-2 (CANN)	Engine switch off	54 to 69 Ω	Below 53 Ω: Short in line
   G103-3 (CANP) - G103-2 (CANN)	Engine switch off	54 to 69 Ω	Higher than 70 Ω: Open in CAN main bus line
   G103-3 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher	Below 6 kΩ: +B short
   G103-2 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher	Below 6 kΩ: +B short
   G103-3 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher	Below 200 Ω: Ground short
   G103-2 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher	Below 200 Ω: Ground short

   Text in Illustration

   *a	Component with harness connected (No. 8 Junction Connector)
   *b	Front view of DLC3

   Result

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

B	Go to step 9
C	Go to step 24

A

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

1. Disconnect the G96 No. 3 junction connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-4 (CANH) - G96-15 (CANL)	Engine switch off	108 to 132 Ω

   Text in Illustration

   *a	Rear view of wire harness connector (to No. 3 Junction Connector)

NG	Go to step 5

OK

4.CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 3 JUNCTION CONNECTOR - NO. 8 JUNCTION CONNECTOR)

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-6 (CANH) - G96-17 (CANL)	Engine switch off	108 to 132 Ω

   Text in Illustration

   *a	Rear view of wire harness connector (to No. 3 Junction Connector)

NG	Go to step 7

OK
REPLACE NO. 3 JUNCTION CONNECTOR

5.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

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

1. Disconnect the G63 main body ECU (multiplex network body ECU) connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G63-9 (CANP) - G63-10 (CANN)	Engine switch off	108 to 132 Ω

   Text in Illustration

   *a	Front view of wire harness connector (to Main Body ECU [Multiplex Network Body ECU])

NG	REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO MAIN BODY ECU (CANP, CANN)

OK
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (LandCruiser RM000003WBO05FX.html)

7.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

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

1. Disconnect the G103 No. 8 junction connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G103-3 (CANP) - G103-2 (CANN)	Engine switch off	108 to 132 Ω

   Text in Illustration

   *a	Rear view of wire harness connector (to No. 8 Junction Connector)

NG	REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 JUNCTION CONNECTOR - NO. 3 JUNCTION CONNECTOR)

OK
REPLACE NO. 8 JUNCTION CONNECTOR

9.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - FRONT POWER SEAT SWITCH LH)

NOTICE:

For vehicles without a seat position memory, go to "Check for Short in CAN Bus Wires (No. 3 Junction Connector - Multiplex Tilt and Telescopic ECU)".

1. Disconnect the G96 No. 3 junction connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-2 (CANH) - G96-13 (CANL)	Engine switch off	200 Ω or higher
   G96-2 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-13 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-2 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G96-13 (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

NG	Go to step 14

OK

10.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - MULTIPLEX TILT AND TELESCOPIC ECU)

NOTICE:

For vehicles without a power tilt and telescopic steering column, go to "Check for Short in CAN Bus Wires (No. 3 Junction Connector - Driving Support Switch Control ECU)".

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-3 (CANH) - G96-14 (CANL)	Engine switch off	200 Ω or higher
   G96-3 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-14 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-3 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G96-14 (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

NG	Go to step 16

OK

11.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - DRIVING SUPPORT SWITCH CONTROL ECU)

NOTICE:

For vehicles without a multi-function switch, go to "Check for Short in CAN Bus Wires (No. 3 Junction Connector - Main Body ECU)".

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-5 (CANH) - G96-16 (CANL)	Engine switch off	200 Ω or higher
   G96-5 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-16 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-5 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G96-16 (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

NG	Go to step 18

OK

12.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - MAIN BODY ECU)

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-4 (CANH) - G96-15 (CANL)	Engine switch off	108 to 132 Ω
   G96-4 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-15 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-4 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G96-15 (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

NG	Go to step 20

OK

13.CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - NO. 8 JUNCTION CONNECTOR)

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G96-6 (CANH) - G96-17 (CANL)	Engine switch off	108 to 132 Ω
   G96-6 (CANH) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-17 (CANL) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G96-6 (CANH) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G96-17 (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

NG	Go to step 22

OK
REPLACE NO. 3 JUNCTION CONNECTOR

14.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

15.CHECK FOR SHORT IN CAN BUS WIRES (FRONT POWER SEAT SWITCH LH)

1. Disconnect the b5 front power seat switch LH connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   b5-8 (CANP) - b5-7 (CANN)	Engine switch off	54 to 69 Ω
   b5-8 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
   b5-7 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
   b5-8 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   b5-7 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

   Text in Illustration

   *a	Rear view of wire harness connector (to Front Power Seat Switch LH)
   *b	Front view of DLC3

NG	REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO FRONT POWER SEAT SWITCH LH (CANP, CANN)

OK
REPLACE FRONT POWER SEAT SWITCH LH (LandCruiser RM000004673017X.html)

16.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

17.CHECK FOR SHORT IN CAN BUS WIRES (MULTIPLEX TILT AND TELESCOPIC ECU)

1. Disconnect the G116 multiplex tilt and telescopic ECU connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G116-5 (CANP) - G116-14 (CANN)	Engine switch off	54 to 69 Ω
   G116-5 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G116-14 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G116-5 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G116-14 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

   Text in Illustration

   *a	Rear view of wire harness connector (to Multiplex Tilt and Telescopic ECU)
   *b	Front view of DLC3

NG	REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO MULTIPLEX TILT AND TELESCOPIC ECU (CANP, CANN)

OK
REPLACE MULTIPLEX TILT AND TELESCOPIC ECU (LandCruiser RM0000039SD01GX.html)

18.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

19.CHECK FOR SHORT IN CAN BUS WIRES (DRIVING SUPPORT SWITCH CONTROL ECU)

1. for Automatic Transmission:
   

   
   
   

   1. Disconnect the G163 driving support switch control ECU connector.
      

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

      Standard Resistance:

      Tester Connection	Switch Condition	Specified Condition
      G163-2 (CANP) - G163-3 (CANN)	Engine switch off	54 to 69 Ω
      G163-2 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
      G163-3 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
      G163-2 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
      G163-3 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

      Text in Illustration

      *a	Front view of wire harness connector (to Driving Support Switch Control ECU)
      *b	Front view of DLC3

2. for Manual Transmission:
   

   
   
   

   1. Disconnect the G76 driving support switch control ECU connector.
      

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

      Standard Resistance:

      Tester Connection	Switch Condition	Specified Condition
      G76-9 (CANP) - G76-10 (CANN)	Engine switch off	54 to 69 Ω
      G76-9 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
      G76-10 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
      G76-9 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
      G76-10 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

      Text in Illustration

      *a	Rear view of wire harness connector (to Driving Support Switch Control ECU)
      *b	Front view of DLC3

NG	REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DRIVING SUPPORT SWITCH CONTROL ECU (CANP, CANN)

OK
REPLACE DRIVING SUPPORT SWITCH CONTROL ECU (LandCruiser RM00000466X024X.html)

20.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

21.CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)

1. Disconnect the G63 main body ECU (multiplex network body ECU) connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G63-9 (CANP) - G63-10 (CANN)	Engine switch off	108 to 132 Ω
   G63-9 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G63-10 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G63-9 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G63-10 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

   Text in Illustration

   *a	Front view of wire harness connector (to Main Body ECU [Multiplex Network Body ECU])
   *b	Front view of DLC3

NG	REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO MAIN BODY ECU (CANP, CANN)

OK
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (LandCruiser RM000003WBO05FX.html)

22.CONNECT CONNECTOR

1. Reconnect the G96 No. 3 junction connector.
   

NEXT

23.CHECK FOR SHORT IN CAN BUS WIRES (NO. 8 JUNCTION CONNECTOR)

1. Disconnect the G103 No. 8 junction connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   G103-3 (CANP) - G103-2 (CANN)	Engine switch off	108 to 132 Ω
   G103-3 (CANP) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G103-2 (CANN) - G48-4 (CG)	Engine switch off	200 Ω or higher
   G103-3 (CANP) - G48-16 (BAT)	Engine switch off	6 kΩ or higher
   G103-2 (CANN) - G48-16 (BAT)	Engine switch off	6 kΩ or higher

   Text in Illustration

   *a	Rear view of wire harness connector (to No. 8 Junction Connector)
   *b	Front view of DLC3

NG	REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 JUNCTION CONNECTOR - NO. 3 JUNCTION CONNECTOR)

OK
REPLACE NO. 8 JUNCTION CONNECTOR

24.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND)

1. Connect the cable to the negative (-) battery terminal.
   

   
   
   
   
   

   Text in Illustration

   *a

   Rear view of wire harness connector (to Main Body ECU [Multiplex Network Body ECU])

   *b

   Front view of wire harness connector (to Main Body ECU [Multiplex Network Body ECU])

   NOTICE:

   When disconnecting the cable, some systems need to be initialized after the cable is reconnected (LandCruiser RM000003YMF011X.html).

2. Remove the main body ECU (multiplex network body ECU) (LandCruiser RM000003WBO05FX.html).
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   G63-3 (GND2) - Body ground	Always	Below 1 Ω
   A-11 (GND1) - Body ground	Always	Below 1 Ω

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

   Standard Voltage:

   Tester Connection	Condition	Specified Condition
   A-30 (BECU) - Body ground	Always	11 to 14 V
   A-31 (ALTB) - Body ground	Always	11 to 14 V
   A-29 (ACC) - Body ground	Engine switch on (ACC)	11 to 14 V
   A-32 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (LandCruiser RM000003WBO05FX.html)