CAN COMMUNICATION SYSTEM(for RHD with Entry and Start System), Diagnostic DTC:U1002

DTC Code	DTC Name
U1002	Lost Communication with Gateway Module (Power Management2)

DESCRIPTION

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


*1	Air Conditioning Amplifier Assembly
*2	No. 3 Junction Connector
*3	Power Management Control ECU

CAUTION / NOTICE / HINT

Note

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

Tech Tips

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

PROCEDURE

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.
  Note
  - 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 Click here.
  - When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.
NEXT

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

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

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

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

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

CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY AND GROUND) Click here

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

Text in Illustration

*a
Rear view of wire harness connector

(to No. 3 Junction Connector)

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

CONNECT CONNECTOR Click here

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

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

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

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
G98-11 (CANH) - G98-22 (CANL)	Engine switch off	108 to 132 Ω

REPLACE NO. 3 JUNCTION CONNECTOR

CONNECT CONNECTOR Click here

CONNECT CONNECTOR
1. Reconnect the G98 No. 3 junction connector.
NEXT

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

Text in Illustration

*a
Front view of wire harness connector

(to 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

REPLACE ECM Click here

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

CONNECT CONNECTOR
1. Reconnect the G98 No. 3 junction connector.
NEXT

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

Text in Illustration

*a
Rear view of wire harness connector

(to 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

REPLACE POWER MANAGEMENT CONTROL ECU Click here

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

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

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

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

CONNECT CONNECTOR Click here

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

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

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

CONNECT CONNECTOR Click here

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

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

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

REPLACE NO. 3 JUNCTION CONNECTOR

CONNECT CONNECTOR Click here

CONNECT CONNECTOR
1. Reconnect the G98 No. 3 junction connector.
NEXT

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

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

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

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

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

CONNECT CONNECTOR
1. Reconnect the G98 No. 3 junction connector.
NEXT

CHECK FOR SHORT IN CAN BUS WIRES (ECM)

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

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

REPLACE ECM Click here

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

CONNECT CONNECTOR
1. Reconnect the G98 No. 3 junction connector.
NEXT

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

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

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

REPLACE POWER MANAGEMENT CONTROL ECU Click here

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

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

Text in Illustration

*a
Rear view of wire harness connector

(to Power Management Control ECU)

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

Note

When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.
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

REPLACE POWER MANAGEMENT CONTROL ECU Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR