Toyota Corolla Cross: Main Body ECU Communication Stop Mode

DESCRIPTION

WIRING DIAGRAM

w/ Power Back Door

w/o Power Back Door

CAUTION / NOTICE / HINT

CAUTION:

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

NOTICE:

• 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.

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• 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 (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
• After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

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• When disconnecting and reconnecting the auxiliary battery.

  HINT:

  When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

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• Some parts must be initialized and set when replacing or removing and installing parts.

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

  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 as normal.

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• Inspect the fuses for circuits related to this system before performing the following procedure.
• Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

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HINT:

• Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
• When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

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

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

(c) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition I85-2 (CANH) - I85-1 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

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

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

OK

(a) Remove the main body ECU (multiplex network body ECU).

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

(c) Measure the voltage according to the value(s) in the table below. Standard Voltage: Tester Connection Switch Condition Specified Condition MB-26 (BECU) - Body ground Ignition switch off 11 to 14 V NOTICE: Perform this inspection with the wire harness connected to the power distribution box assembly.

*1 Power Distribution Box Assembly

OK

CHECK ECU POWER SOURCE CIRCUIT

NG

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

(b) Disconnect the power distribution box assembly connector.

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

(d) Measure the voltage according to the value(s) in the table below. Standard Voltage: Tester Connection Switch Condition Specified Condition 8E-23 - Body ground Ignition switch off 11 to 14 V

*a Front view of wire harness connector (to Power Distribution Box Assembly)

OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (BECU SIGNAL CIRCUIT)

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