DESCRIPTION
The network gateway ECU stores this DTC when no signals can be received from the ECUs that have been memorized as those connected to the WIL bus circuit.
When the network gateway ECU receives a response signal from the ECUs connected to the WIL bus circuit, the network gateway ECU recognizes and memorizes that the ECU is connected to the WIL bus circuit. Based on this memorized data, the network gateway ECU monitors for malfunctions in the ECUs connected to the WIL bus circuit when communicating with those ECUs. If the network gateway ECU cannot receive response signals from the ECUs that have been memorized as those connected to the WIL bus circuit, the network gateway 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 [CAN branch wire]/CANL [CAN branch wire] of the ECU and/or sensor is open).
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| U1002 | Lost communication with gateway module (WIL bus) |
|
For vehicles with a pre-crash intelligent headrest.
*1: for 5-Passenger with Ottoman
*2: except 5-Passenger with Ottoman
WIRING DIAGRAM
INSPECTION PROCEDURE
Tech Tips
Operating the power switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
PROCEDURE
PRECAUTION
Note
After turning the power switch off, waiting time may be required before disconnecting the cable from the auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the auxiliary battery terminal notice before proceeding with work Click here.
| NEXT |
|
DISCONNECT CABLE FROM NEGATIVE AUXILIARY BATTERY TERMINAL
Disconnect the cable from the negative (-) auxiliary 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 (-) auxiliary battery terminal to disable the SRS system.
Note
When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.
| NEXT |
|
CHECK CAN BUS WIRE (CAN MAIN WIRE FOR DISCONNECTION, BUS LINE FOR SHORT CIRCUIT)
| *a | Component with harness connected (Active Headrest Control ECU RH [Front Seat Headrest Assembly RH]) |
| *b | Front view of DLC3 |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| NG
|
A |
| NG
|
B |
| OK | C |
| B |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NETWORK GATEWAY ECU) Click here |
| C |
|
CHECK HARNESS AND CONNECTOR (NETWORK GATEWAY ECU - BATTERY AND BODY GROUND) Click here |
| A |
|
CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
Disconnect the No. 13 junction connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| OK (for 5-Passenger with Ottoman) | A |
| OK (except 5-Passenger with Ottoman) | B |
| NG | C |
| B |
|
CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - NO. 16 JUNCTION CONNECTOR) Click here |
| C |
|
CONNECT CONNECTOR Click here |
| A |
|
CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU LH)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
CONNECT CONNECTOR Click here |
| OK |
|
REPLACE NO. 13 JUNCTION CONNECTOR
CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - NO. 16 JUNCTION CONNECTOR)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
CONNECT CONNECTOR Click here |
| OK |
|
REPLACE NO. 13 JUNCTION CONNECTOR
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS MAIN WIRE (ACTIVE HEADREST CONTROL ECU RH)
| *a | Rear view of wire harness connector (to Active Headrest Control ECU RH [Front Seat Headrest Assembly RH]) |
Disconnect the active headrest control ECU RH (front seat headrest assembly RH) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU RH (ACTIVE HEADREST CONTROL ECU RH - NO. 13 JUNCTION CONNECTOR) |
| OK |
|
REPLACE ACTIVE HEADREST CONTROL ECU RH (FRONT SEAT HEADREST ASSEMBLY RH) Click here
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS MAIN WIRE (ACTIVE HEADREST CONTROL ECU LH)
| *a | Rear view of wire harness connector (to Active Headrest Control ECU LH [Front Seat Headrest Assembly LH]) |
Disconnect the active headrest control ECU LH (front seat headrest assembly LH) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU LH (ACTIVE HEADREST CONTROL ECU LH - NO. 13 JUNCTION CONNECTOR) |
| OK |
|
REPLACE ACTIVE HEADREST CONTROL ECU LH (FRONT SEAT HEADREST ASSEMBLY LH) Click here
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 16 JUNCTION CONNECTOR)
| *a | Rear view of wire harness connector (to No. 16 Junction Connector) |
Disconnect the No. 16 junction connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 16 JUNCTION CONNECTOR - NO. 13 JUNCTION CONNECTOR) |
| OK |
|
REPLACE NO. 16 JUNCTION CONNECTOR
CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NETWORK GATEWAY ECU)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
| *b | Front view of DLC3 |
Disconnect the No. 13 junction connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
CONNECT CONNECTOR Click here |
| OK |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
| *b | Front view of DLC3 |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| OK (for 5-Passenger with Ottoman) | A |
| OK (except 5-Passenger with Ottoman) | B |
| NG | C |
| B |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NO. 16 JUNCTION CONNECTOR) Click here |
| C |
|
CONNECT CONNECTOR Click here |
| A |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU LH)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
| *b | Front view of DLC3 |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
CONNECT CONNECTOR Click here |
| OK |
|
REPLACE NO. 13 JUNCTION CONNECTOR
CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NO. 16 JUNCTION CONNECTOR)
| *a | Rear view of wire harness connector (to No. 13 Junction Connector) |
| *b | Front view of DLC3 |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
CONNECT CONNECTOR Click here |
| OK |
|
REPLACE NO. 13 JUNCTION CONNECTOR
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU)
| *a | Front view of wire harness connector (to Network Gateway ECU) |
| *b | Front view of DLC3 |
Disconnect the network gateway ECU connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO NETWORK GATEWAY ECU (CA2H, CA2L) |
| OK |
|
REPLACE NETWORK GATEWAY ECU
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (ACTIVE HEADREST CONTROL ECU RH)
| *a | Rear view of wire harness connector (to Active Headrest Control ECU RH [Front Seat Headrest Assembly RH]) |
| *b | Front view of DLC3 |
Disconnect the headrest control ECU RH (front seat headrest assembly RH) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU RH (CA3H, CA3L) |
| OK |
|
REPLACE ACTIVE HEADREST CONTROL ECU RH (FRONT SEAT HEADREST ASSEMBLY RH) Click here
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (ACTIVE HEADREST CONTROL ECU LH)
| *a | Rear view of wire harness connector (to Active Headrest Control ECU LH [Front Seat Headrest Assembly LH]) |
| *b | Front view of DLC3 |
Disconnect the headrest control ECU LH (front seat headrest assembly LH) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU LH (CA3H, CA3L) |
| OK |
|
REPLACE ACTIVE HEADREST CONTROL ECU LH (FRONT SEAT HEADREST ASSEMBLY LH) Click here
CONNECT CONNECTOR
Reconnect the L120 No. 13 junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 16 JUNCTION CONNECTOR)
| *a | Rear view of wire harness connector (to No. 16 Junction Connector) |
| *b | Front view of DLC3 |
Disconnect the No. 16 junction connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 16 JUNCTION CONNECTOR - NO. 13 JUNCTION CONNECTOR) |
| OK |
|
REPLACE NO. 16 JUNCTION CONNECTOR
CHECK HARNESS AND CONNECTOR (NETWORK GATEWAY ECU - BATTERY AND BODY GROUND)
| *a | Front view of wire harness connector (to Network Gateway ECU) |
Connect the cable to the negative (-) auxiliary battery terminal.
Note
When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.
Disconnect the network gateway ECU connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
REPLACE NETWORK GATEWAY ECU