NETWORKING CAN COMMUNICATION SYSTEM Main Body ECU Communication Stop Mode

DESCRIPTION

Detection Item	Symptom	Trouble Area
Main Body ECU Communication Stop Mode	Either condition is met: · "Main Body" is not displayed on the CAN Bus Check screen of the GTS Click here() · Communication system DTCs (DTCs that start with U) that correspond to "Main Body ECU Communication Stop Mode" in "DTC Combination Table" are output Click here()	· Main body ECU (multiplex network body ECU) branch line or connector · Power source circuit of main body ECU (multiplex network body ECU) or instrument panel junction block assembly · Main body ECU (multiplex network body ECU) ground circuit or instrument panel junction block assembly · Main body ECU (multiplex network body ECU) or instrument panel junction block assembly

WIRING DIAGRAM

1.5,1.094 1.677,0.104 1.677,0.104 1.781,0.104 true 3.656,1.094 4.021,0.104 4.021,0.104 4.125,0.104 true 0.052,0.052 1.042,0.448 0.99,0.396 12 false V Bus: 5.094,0.417 5.708,0.615 0.615,0.198 10 false DLC3 1.844,0.01 4.063,0.292 2.219,0.281 10 false No. 1 CAN Junction Connector 4.229,0.01 6.448,0.292 2.219,0.281 10 false No. 2 CAN Junction Connector 0.521,2.104 1.135,2.302 0.615,0.198 10 false 120 Ω 6.271,2.104 6.885,2.302 0.615,0.198 10 false 120 Ω 0.469,2.49 0.927,2.688 0.458,0.198 10 false ECM 5.885,2.479 7.094,3.021 1.208,0.542 10 false Combination Meter Assembly 2.146,3.833 3.979,4.031 1.833,0.198 10 false Trouble Area 1.052,4.469 3.052,4.75 2,0.281 10 false : CAN Main Bus Line (CANH) 1.063,4.781 5.042,4.979 3.979,0.198 10 false : CAN Main Bus Line (CANL) 1.063,5.104 4.729,5.302 3.667,0.198 10 false : CAN Branch Line (CANH) 1.063,5.406 4.729,5.604 3.667,0.198 10 false : CAN Branch Line (CANL) 3.958,4.677 5.615,5.198 1.656,0.521 10 false Main Body ECU (Multiplex Network Body ECU) 6.302,4.594 6.917,4.792 0.615,0.198 10 false CANL 5.802,4.594 6.417,4.792 0.615,0.198 10 false CANH 6.302,4.365 6.76,4.563 0.458,0.198 10 false E31 5.906,4.365 6.365,4.563 0.458,0.198 10 false E31 5.844,4.167 6.156,4.365 0.313,0.198 10 false 14 6.438,4.167 6.75,4.365 0.313,0.198 10 false 13

1.188,1.219 2.26,1.417 1.073,0.198 10 false Battery 0.313,1.729 1.844,2.75 1.531,1.021 10 false Certification ECU (Smart Key ECU Assembly)*1 or Ignition Switch*2 1.115,5.656 2.188,5.854 1.073,0.198 10 false Battery 1.781,5.833 3.469,6.031 1.688,0.198 10 false ECU-B NO. 1 2.26,1.406 2.719,1.604 0.458,0.198 10 false ALT 4.094,7.531 5.927,7.729 1.833,0.198 10 false Trouble Area 5.385,6.792 7.031,7.302 1.646,0.51 10 false Main Body ECU (Multiplex Network Body ECU) 2.667,6.104 5.438,6.344 2.771,0.24 10 false Instrument Panel Junction Block Assembly 2.802,1.25 3.115,1.448 0.313,0.198 10 false 3B 2.813,2.99 3.125,3.188 0.313,0.198 10 false 3D 2.813,1.719 3.125,1.917 0.313,0.198 10 false 3D 2.813,4.75 3.125,4.948 0.313,0.198 10 false 3D 2.802,3.865 3.115,4.063 0.313,0.198 10 false 3C 2.813,4.323 3.125,4.521 0.313,0.198 10 false 3C 2.802,5.188 3.115,5.385 0.313,0.198 10 false 3C 2.813,5.688 3.125,5.885 0.313,0.198 10 false 3A 2.854,1.042 3.01,1.24 0.156,0.198 10 false 1 2.823,1.521 3.135,1.719 0.313,0.198 10 false 26 2.833,2.792 3.146,2.99 0.313,0.198 10 false 25 2.833,3.656 3.146,3.854 0.313,0.198 10 false 37 2.833,4.125 3.146,4.323 0.313,0.198 10 false 51 2.813,4.563 3.125,4.76 0.313,0.198 10 false 12 2.854,4.99 3.01,5.188 0.156,0.198 10 false 9 2.844,5.469 3.156,5.667 0.313,0.198 10 false 43 5.458,1.25 5.771,1.448 0.313,0.198 10 false MB 5.469,4.323 5.781,4.521 0.313,0.198 10 false MB 5.469,5.188 5.781,5.385 0.313,0.198 10 false MB 5.469,5.688 5.781,5.885 0.313,0.198 10 false MB 4.677,1.396 5.135,1.594 0.458,0.198 10 false ACC 4.375,2.896 6.208,3.094 1.833,0.198 10 false ECU-IG NO. 4 5.833,1.24 6.292,1.438 0.458,0.198 10 false ACC 5.833,4.323 6.146,4.521 0.313,0.198 10 false IG 5.833,5.188 6.448,5.385 0.615,0.198 10 false GND1 5.823,5.677 6.438,5.875 0.615,0.198 10 false BECU 5.49,1.042 5.802,1.24 0.313,0.198 10 false 29 5.51,4.125 5.823,4.323 0.313,0.198 10 false 32 5.51,4.979 5.823,5.177 0.313,0.198 10 false 11 5.5,5.479 5.813,5.677 0.313,0.198 10 false 30 3.469,1.99 4.458,2.313 0.99,0.323 10 false ACC Relay 3.49,3.25 4.125,3.635 0.635,0.385 10 false IG1 NO. 3 Relay 0.323,3 1.854,4.021 1.531,1.021 10 false Certification ECU (Smart Key ECU Assembly)*1 or Ignition Switch*2 0.302,7.552 3,7.948 2.698,0.396 10 false *1: w/ Smart Entry and Start System 0.302,7.938 3,8.333 2.698,0.396 10 false *2: w/o Smart Entry and Start System

CAUTION / NOTICE / HINT

CAUTION:: When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:: ·

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 or any 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.

·

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 notices before proceeding with work.

Click hereGeneral>INTRODUCTION>REPAIR INSTRUCTION>PRECAUTION

·

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 herePower Source / Network>NETWORKING>CAN COMMUNICATION SYSTEM>HOW TO PROCEED WITH TROUBLESHOOTING

·

After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

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DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.

·

After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed.

Click herePower Source / Network>NETWORKING>CAN COMMUNICATION SYSTEM>DIAGNOSIS SYSTEM

·

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

HINT:: ·

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

1.CHECK FOR OPEN IN CAN BUS LINES (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) BRANCH LINE)

Disconnect the cable from the negative (-) battery terminal.

1.479,0.51 1.875,0.865 0.396,0.354 1.802,1.865 2,0.792 2,0.792 2.385,0.792 true 1.927,1.885 2.052,1.104 2.052,1.104 2.292,1.104 true 2.375,1.021 2.99,1.219 0.615,0.198 10 false CANH 2.458,0.708 3.073,0.906 0.615,0.198 10 false CANL 1.552,0.594 2.167,0.792 0.615,0.198 10 false E31 0.104,0.094 0.719,0.292 0.615,0.198 10 false *a

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

Disconnect the E31 main body ECU (multiplex network body ECU) connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
E31-14 (CANH) - E31-13 (CANL)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

Result:

Result
OK
NG

2.CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

2.CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

Disconnect the 3C and 3D instrument panel junction block assembly connectors.

1.438,0.115 1.833,0.385 0.396,0.271 1.49,1.813 1.885,2.083 0.396,0.271 2.771,2.573 2.625,1.938 2.625,1.938 2.51,1.938 true 2.615,0.323 2.521,0.323 2.521,0.323 2.344,0.927 true 0.063,0.073 0.375,0.271 0.313,0.198 10 false *a 1.552,0.146 1.865,0.344 0.313,0.198 10 false 3C 1.604,1.854 1.917,2.052 0.313,0.198 10 false 3D 2.083,1.854 2.698,2.052 0.615,0.198 10 false GND1 2.688,0.229 3.302,0.427 0.615,0.198 10 false GND1

*a	Front view of wire harness connector (to Instrument Panel Junction Block Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3C-9 (GND1) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω
3D-12 (GND1) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

Disconnect the 3A instrument panel junction block assembly connector.

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

1.469,0.688 1.958,0.948 0.49,0.26 0.99,2.49 1.094,2.49 1.094,2.49 1.323,1.885 true 0.125,0.104 0.469,0.365 0.344,0.26 10 false *a 1.625,0.719 2.052,0.99 0.427,0.271 10 false 3A 0.563,2.396 1.094,2.677 0.531,0.281 10 false BECU

*a	Front view of wire harness connector (to Instrument Panel Junction Block Assembly)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
3A-43 (BECU) - Body ground	Always	11 to 14 V

Result:

Result
OK
NG

3.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1 NO. 3 RELAY AND ACC RELAY)

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

3.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1 NO. 3 RELAY AND ACC RELAY)

Inspect the IG1 No. 3 relay and ACC relay of the instrument panel junction block assembly.

IG signal circuit:

Click hereVehicle Interior>LIGHTING (INT)>LIGHTING SYSTEM>IG Signal Circuit

ACC signal circuit:

Click hereVehicle Interior>LIGHTING (INT)>LIGHTING SYSTEM>ACC Signal Circuit

HINT:: If the IG signal circuit and ACC signal circuit have no problem, replace the main body ECU (multiplex network body ECU).

Result:

Result
OK
NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Click herePower Source / Network>POWER DISTRIBUTION>MAIN BODY ECU>REMOVAL

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

Click herePower Source / Network>POWER DISTRIBUTION>MAIN BODY ECU>REMOVAL