DETERMINING SHORT TO POWER SUPPLY LOCATION (CAN-BUS No.7)


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Caution
•  Perform the following malfunction diagnosis only when it is diagnosed with a short to power supply by CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW.)

System Wiring Diagram

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Determination Procedure

Caution
•  When disconnecting the connector, verify that there is no looseness, damage, deformation, corrosion, or poor connection of the connector terminals.
•  When inspecting the connector, touch it with a paper clip or similar thin pin without directly inserting a tester probe into the terminal.
•  Disconnect the negative battery terminal before performing any work that requires handling of connectors.

Step

Inspection

Action

1
INSPECT CAN LINE BETWEEN CONNECTOR C-41 AND BODY CONTROL MODULE (BCM) FOR SHORT TO POWER SUPPLY
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Disconnect the connector C-41.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off).
•  Measure the voltage at body control module (BCM) terminals 4R and 4Q.
•  Is the voltage between 1.5—3.5 V?
Yes
Go to Step 3.
No
Go to the next step.
2
INSPECT BODY CONTROL MODULE (BCM) FOR SHORT TO POWER SUPPLY
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Disconnect the connector 4 which has body control module (BCM) terminals 4R and 4Q.
•  Connect the connector C-41.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off).
•  Measure the voltage at body control module (BCM) terminals 4R and 4Q (wiring harness side).
•  Is the voltage between 1.5—3.5 V?
Yes
Replace the body control module (BCM) because there is a short to the power supply in the body control module (BCM).
No
Repair or replace the wiring harness between the body control module (BCM) and connector C-41 because the wiring harness is shorted to the power supply.
3
INSPECT CAN LINE BETWEEN AUDIO AMPLIFIER AND CONNECTOR C-41 FOR SHORT TO POWER SUPPLY
•  Measure the voltage at audio amplifier terminals 2N and 2M. (With Bose® type audio)
•  Measure the voltage at audio amplifier terminals 1Q and 1S. (Without Bose® type audio)
•  Is the voltage between 1.5—3.5 V?
Yes
Go to Step 5.
No
Go to the next step.
4
INSPECT AUDIO AMPLIFIER FOR SHORT TO POWER SUPPLY
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Disconnect the audio amplifier connector.
•  Connect the connector C-41.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off).
•  Measure the voltage at body control module (BCM) terminals 4R and 4Q.
•  Is the voltage between 1.5—3.5 V?
Yes
Replace the audio amplifier because there is a short to the power supply in the audio amplifier.
No
Repair or replace the wiring harness between the audio amplifier and connector C-41 because the wiring harness is shorted to the power supply.
5
INSPECT CAN LINE BETWEEN CONNECTOR C-41 AND CONNECTOR C-13 FOR SHORT TO POWER SUPPLY
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Connect the connector C-41.
•  Disconnect the connector C-13.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off).
•  Measure the voltage at body control module (BCM) terminals 4R and 4Q.
•  Is the voltage between 1.5—3.5 V?
Yes
Go to the next step.
No
Repair or replace the wiring harness between the connector C-41 and connector C-13 because the wiring harness is shorted to the power supply.
6
INSPECT CONNECTIVITY MASTER UNIT (CMU) FOR SHORT TO POWER SUPPLY
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Disconnect the connectivity master unit (CMU) connector.
•  Connect the connector C-13.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off).
•  Measure the voltage at body control module (BCM) terminals 4R and 4Q.
•  Is the voltage between 1.5—3.5 V?
Yes
Replace the connectivity master unit (CMU) because there is a short to the power supply in the connectivity master unit (CMU).
No
Repair or replace the wiring harness between the connectivity master unit (CMU) and connector C-13 because the wiring harness is shorted to the power supply.