| DTC Code | DTC Name |
|---|---|
| U1002 | Lost Communication with Gateway Module (Main Body) |
DESCRIPTION
The main body ECU (multiplex network body ECU) will store this DTC when no signals can be received from the ECUs that have been memorized as those that are connected to sub bus 1.
When the main body ECU (multiplex network body ECU) receives a response signal from the ECUs connected to sub bus 1, the main body ECU (multiplex network body ECU) recognizes and memorizes that the ECU is connected to sub bus 1. Based on this memorized data, the main body ECU (multiplex network body ECU) monitors for malfunctions in the ECUs connected to sub bus 1 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 sub bus 1, the main body ECU (multiplex network body ECU) determines that a malfunction exists.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| U1002 | Main body ECU (multiplex network body ECU) cannot receive signals from all ECUs that have been memorized as those connected to sub bus 1. |
|
*1: w/ Memory
*2: w/ Power Tilt and Power Telescopic Steering Column System
*3: w/ Power Back Door System
*4: w/ Tail Gate Closer System
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key, switches or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output Click here.
After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notice before proceeding with work Click here.
After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
After the repair, perform CAN Bus Check and check that all the ECUs and sensors connected to the CAN communication system are displayed Click here.
Tech Tips
Operating the ignition 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
CHECK SUB BUS 1
| *a | Component with harness connected (Main Body ECU [Multiplex Network Body ECU]) |
| *b | Front view of DLC3 |
Disconnect the cable from the negative (-) battery terminal.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| OK | A |
| NG (Open circuit in CAN main bus wire) | B |
| NG (Short circuit between bus wires) | C |
| NG
|
D |
| B |
|
CHECK FOR OPEN IN CAN BUS WIRE (MAIN BODY ECU) Click here |
| C |
|
CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU) Click here |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU) Click here |
| A |
|
CHECK FOR DTC
Clear the DTCs Click here.
Recheck for DTCs and check that no DTCs are output Click here.
| OK |
|---|
| DTC U1002 is not output. |
| OK |
|
USE SIMULATION METHOD TO CHECK Click here |
| NG |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
CHECK FOR OPEN IN CAN BUS WIRE (MAIN BODY ECU)
| *a | Rear view of wire harness connector (to Main Body ECU [Multiplex Network Body ECU]) |
Disconnect the main body ECU (multiplex network body ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
| NG |
|
CONNECT CONNECTOR
Reconnect the E117 main body ECU (multiplex network body ECU) connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS WIRE (NO. 3 CAN JUNCTION TERMINAL)
| *a | Rear view of wire harness connector (to No. 3 CAN Junction Terminal) |
Disconnect the No. 3 CAN junction terminal connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE NO. 3 CAN JUNCTION TERMINAL |
| NG |
|
CONNECT CONNECTOR
Reconnect the L69 No. 3 CAN junction terminal connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS WIRE (NO. 7 CAN JUNCTION CONNECTOR)
Disconnect the No. 7 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 7 CAN Junction Connector) |
*b | to No. 8 CAN Junction Connector |
| *c | to Main Body ECU (Multiplex Network Body ECU) | - | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to Main body ECU CAN main wire) | B |
| NG (to No. 8 CAN junction connector CAN main wire) | C |
| A |
|
REPLACE NO. 7 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR - MAIN BODY ECU) |
| C |
|
CONNECT CONNECTOR
Reconnect the E134 No. 7 CAN junction connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS WIRE (NO. 8 CAN JUNCTION CONNECTOR)
Disconnect the No. 8 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 8 CAN Junction Connector) |
*b | to No. 7 CAN Junction Connector |
| *c | to No. 9 CAN Junction Connector | - | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to No. 7 CAN junction connector CAN main wire) | B |
| NG (to No. 9 CAN junction connector CAN main wire) | C |
| A |
|
REPLACE NO. 8 CAN JUNCTION CONNECT |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 CAN JUNCTION CONNECTOR - NO. 7 CAN JUNCTION CONNECTOR) |
| C |
|
CONNECT CONNECTOR
Reconnect the E136 No. 8 CAN junction connector.
| NEXT |
|
CHECK FOR OPEN IN CAN BUS WIRE (NO. 9 CAN JUNCTION CONNECTOR)
Disconnect the No. 9 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 9 CAN Junction Connector) |
*b | to No. 8 CAN Junction Connector |
| *c | to No. 3 CAN Junction Terminal | - | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to No. 3 CAN junction terminal CAN main wire) | B |
| NG (to No. 8 CAN junction connector CAN main wire) | C |
| A |
|
REPLACE NO. 9 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION TERMINAL) |
| C |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 8 CAN JUNCTION CONNECTOR) |
CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)
| *a | Rear view of wire harness connector (to Main Body ECU [Multiplex Network Body ECU]) |
Disconnect the main body ECU (multiplex network body ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
| NG |
|
CONNECT CONNECTOR
Reconnect the E117 main body ECU (multiplex network body ECU) connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 CAN JUNCTION TERMINAL)
| *a | Rear view of wire harness connector (to No. 3 CAN Junction Terminal) |
Disconnect the No. 3 CAN junction terminal connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE NO. 3 CAN JUNCTION TERMINAL |
| NG |
|
CONNECT CONNECTOR
Reconnect the L69 No. 3 CAN junction terminal connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 CAN JUNCTION CONNECTOR)
Disconnect the No. 7 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 7 CAN Junction Connector) |
*b | to No. 8 CAN Junction Connector |
| *c | to Main Body ECU (Multiplex Network Body ECU) | *d | to Outer Mirror Control ECU Assembly LH (w/ Memory) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*: w/ Memory
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to Main body ECU CAN main wire) | B |
| NG (to No. 8 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wire) | D |
| A |
|
REPLACE NO. 7 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR - MAIN BODY ECU) |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) Click here |
| C |
|
CONNECT CONNECTOR
Reconnect the E134 No. 7 CAN junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 8 CAN JUNCTION CONNECTOR)
Disconnect the No. 8 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 8 CAN Junction Connector) |
*b | to No. 7 CAN Junction Connector |
| *c | to No. 9 CAN Junction Connector | *d | to Outer Mirror Control ECU Assembly RH (w/ Memory) |
| *e | to Power Seat Switch Assembly (w/ Memory) | *f | to Multiplex Tilt and Telescopic ECU (w/ Power Tilt and Power Telescopic Steering Column System) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*1: w/ Memory
*2: w/ Power Tilt and Power Telescopic Steering Column System
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to No. 7 CAN junction connector CAN main wire) | B |
| NG (to No. 9 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wire) | D |
| A |
|
REPLACE NO. 8 CAN JUNCTION CONNECT |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 CAN JUNCTION CONNECTOR - NO. 7 CAN JUNCTION CONNECTOR) |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) Click here |
| C |
|
CONNECT CONNECTOR
Reconnect the E136 No. 8 CAN junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 9 CAN JUNCTION CONNECTOR)
Disconnect the No. 9 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 9 CAN Junction Connector) |
*b | to No. 8 CAN Junction Connector |
| *c | to No. 3 CAN Junction Terminal | *d | to Power Back Door Unit Assembly (Power Back Door ECU) (w/ Power Back Door System) |
| *e | to No. 2 Main Body ECU (w/ Tail Gate Closer System) | - | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*1: w/ Power Back Door System
*2: w/ Tail Gate Closer System
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to No. 3 CAN junction terminal CAN main wire) | B |
| NG (to No. 8 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wire) | D |
| A |
|
REPLACE NO. 9 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION TERMINAL) |
| C |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 8 CAN JUNCTION CONNECTOR) |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR)
| *a | Component with harness connected (Main Body ECU [Multiplex Network Body ECU]) |
Reconnect the CAN junction connector.
Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the short circuited branch line is connected.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE CORRESPONDING ECU OR SENSOR |
| NG |
|
REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRE OR CONNECTOR |
CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)
| *a | Rear view of wire harness connector (Main Body ECU [Multiplex Network Body ECU]) |
| *b | Front view of DLC3 |
Disconnect the main body ECU (multiplex network body ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
| NG |
|
CONNECT CONNECTOR
Reconnect the E117 main body ECU (multiplex network body ECU) connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 CAN JUNCTION TERMINAL)
| *a | Rear view of wire harness connector (to No. 3 CAN Junction Terminal) |
| *b | Front view of DLC3 |
Disconnect the No. 3 CAN junction terminal connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE NO. 3 CAN JUNCTION TERMINAL |
| NG |
|
CONNECT CONNECTOR
Reconnect the L69 No. 3 CAN junction terminal connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 CAN JUNCTION CONNECTOR)
Disconnect the No. 7 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 7 CAN Junction Connector) |
*b | Front view of DLC3 |
| *c | to No. 8 CAN Junction Connector | *d | to Main Body ECU (Multiplex Network Body ECU) |
| *e | to Outer Mirror Control ECU Assembly LH (w/ Memory) | - | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*: w/ Memory
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to Main body ECU CAN main wire) | B |
| NG (to No. 8 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wire) | D |
| A |
|
REPLACE NO. 7 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR - MAIN BODY ECU) |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) Click here |
| C |
|
CONNECT CONNECTOR
Reconnect the E134 No. 7 CAN junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 8 CAN JUNCTION CONNECTOR)
Disconnect the No. 8 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 8 CAN Junction Connector) |
*b | Front view of DLC3 |
| *c | to No. 7 CAN Junction Connector | *d | to No. 9 CAN Junction Connector |
| *e | to Outer Mirror Control ECU Assembly RH (w/ Memory) | *f | to Power Seat Switch Assembly (w/ Memory) |
| *g | to Multiplex Tilt and Telescopic ECU (w/ Power Tilt and Power Telescopic Steering Column System) | - | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*1: w/ Memory
*2: w/ Power Tilt and Power Telescopic Steering Column System
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to No. 7 CAN junction connector CAN main wire) | B |
| NG (to No. 9 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wire) | D |
| A |
|
REPLACE NO. 8 CAN JUNCTION CONNECT |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 CAN JUNCTION CONNECTOR - NO. 7 CAN JUNCTION CONNECTOR) |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) Click here |
| C |
|
CONNECT CONNECTOR
Reconnect the E136 No. 8 CAN junction connector.
| NEXT |
|
CHECK FOR SHORT IN CAN BUS WIRES (NO. 9 CAN JUNCTION CONNECTOR)
Disconnect the No. 9 CAN junction connector.
| *a | Rear view of wire harness connector (to No. 9 CAN Junction Connector) |
*b | Front view of DLC3 |
| *c | to No. 8 CAN Junction Connector | *d | to No. 3 CAN Junction Terminal |
| *e | to Power Back Door Unit Assembly (Power Back Door ECU) (w/ Power Back Door System) | *f | to No. 2 Main Body ECU (w/ Tail Gate Closer System) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*1: w/ Power Back Door System
*2: w/ Tail Gate Closer System
| Result | Proceed to |
|---|---|
| OK | A |
| NG (to No. 3 CAN junction terminal CAN main wire) | B |
| NG (to No. 8 CAN junction connector CAN main wire) | C |
| NG (ECU or sensor CAN branch wire) | D |
| A |
|
REPLACE NO. 9 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION TERMINAL) |
| C |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 CAN JUNCTION CONNECTOR - NO. 8 CAN JUNCTION CONNECTOR) |
| D |
|
CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR)
| *a | Component with harness connected (Main Body ECU [Multiplex Network Body ECU]) |
| *b | Front view of DLC3 |
Reconnect the CAN junction connector.
Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to +B, GND is connected.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| OK |
|
REPLACE CORRESPONDING ECU OR SENSOR |
| NG |
|
REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRE OR CONNECTOR |