DTC B1142:13 [ELECTRICAL SUPPLY UNIT (ESU)]
id0902ff061000
Description |
Ignition switch status mismatch |
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Detection condition
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• The electrical supply unit (ESU) detects the following mismatches.
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Fail-safe
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Not applicable
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Possible cause
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• BCM connector or terminal malfunction
• Electrical supply unit (ESU) connector or terminal malfunction
• BCM power supply circuit (IG1) malfunction
• Electrical supply unit (ESU) power supply circuit (IG1) malfunction
• Short to ground in wiring harness between BCM terminal 2Y and electrical supply unit (ESU) terminal 2I
• Short to power supply in wiring harness between BCM terminal 2Y and electrical supply unit (ESU) terminal 2I
• Open circuit in wiring harness between BCM terminal 2Y and electrical supply unit (ESU) terminal 2I
• BCM malfunction
• Electrical supply unit (ESU) malfunction
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Diagnostic Procedure
Step |
Inspection |
Action |
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1
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INSPECT BCM CONNECTOR CONDITION
• Switch the ignition off.
• Disconnect the negative battery cable.
• Disconnect the BCM connector.
• Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
• Is the connector normal?
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Yes
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Go to the next step.
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No
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Repair or replace the connector, then go to Step 9.
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2
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INSPECT ELECTRICAL SUPPLY UNIT (ESU) CONNECTOR CONDITION
• Disconnect the electrical supply unit (ESU) connector.
• Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
• Is the connector normal?
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Yes
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Go to the next step.
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No
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Repair or replace the connector, then go to Step 9.
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3
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VERIFY BCM POWER SUPPLY (IG1) VOLTAGE
• Connect the negative battery cable.
• Switch the ignition ON (engine off or on).
• Measure the voltage at the BCM terminal 3O (wiring harness-side).
• Is the voltage B+?
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Yes
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Go to Step 8.
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No
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Inspect the METER1 10 A fuse.
• If the fuse is blown:
• If the fuse is damaged:
• If the fuse is normal:
Go to Step 9.
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4
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VERIFY ELECTRICAL SUPPLY UNIT (ESU) POWER SUPPLY (IG1) VOLTAGE
• Measure the voltage at the electrical supply unit (ESU) terminal 1H (wiring harness-side).
• Is the voltage B+?
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Yes
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Go to Step 8.
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No
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Inspect the METER1 10 A fuse.
• If the fuse is blown:
• If the fuse is damaged:
• If the fuse is normal:
Go to Step 9.
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5
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INSPECT LIN COMMUNICATION CIRCUIT BETWEEN BCM AND ELECTRICAL SUPPLY UNIT (ESU) FOR SHORT TO GROUND
• Switch the ignition off.
• Disconnect the negative battery cable.
• Verify that the BCM and electrical supply unit (ESU) connectors are disconnected.
• Inspect for continuity between BCM terminal 2Y (wiring harness-side) and body ground.
• Is there continuity?
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Yes
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Refer to the wiring diagram and verify whether or not there is a common connector between BCM terminal 2Y and electrical supply unit (ESU) terminal 2I.
If there is a common connector:
• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
• Repair or replace the malfunctioning part.
If there is no common connector:
• Repair or replace the wiring harness which has a short to ground.
Go to Step 9.
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No
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Go to the next step.
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6
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INSPECT LIN COMMUNICATION CIRCUIT BETWEEN BCM AND ELECTRICAL SUPPLY UNIT (ESU) FOR SHORT TO POWER SUPPLY
• Verify that the BCM and electrical supply unit (ESU) connectors are disconnected.
• Connect the negative battery cable.
• Switch the ignition ON (engine off or on).
• Measure the voltage at the BCM terminal 2Y (wiring harness-side).
• Is the voltage 0 V?
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Yes
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Go to the next step.
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No
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Refer to the wiring diagram and verify whether or not there is a common connector between BCM terminal 2Y and electrical supply unit (ESU) terminal 2I.
If there is a common connector:
• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
• Repair or replace the malfunctioning part.
If there is no common connector:
• Repair or replace the wiring harness which has a short to power supply.
Go to Step 9.
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7
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INSPECT LIN COMMUNICATION CIRCUIT BETWEEN BCM AND ELECTRICAL SUPPLY UNIT (ESU) FOR OPEN CIRCUIT
• Switch the ignition off.
• Disconnect the negative battery cable.
• Verify that the BCM and electrical supply unit (ESU) connectors are disconnected.
• Inspect the wiring harness for continuity between BCM terminal 2Y (wiring harness-side) and electrical supply unit (ESU) terminal 2I (wiring harness-side).
• Is there continuity?
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Yes
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Go to the next step.
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No
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Refer to the wiring diagram and verify whether or not there is a common connector between BCM terminal 2Y and electrical supply unit (ESU) terminal 2I.
If there is a common connector:
• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
• Repair or replace the malfunctioning part.
If there is no common connector:
• Repair or replace the wiring harness which has an open circuit.
Go to Step 9.
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8
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VERIFY IF MALFUNCTIONING LOCATION IS BCM DEPENDING ON REPEATABILITY
• Always reconnect all disconnected connectors.
• Connect the negative battery cable.
• Clear the DTC for the electrical supply unit (ESU) using the M-MDS.
• Retrieve the electrical supply unit (ESU) DTCs using the M-MDS.
• Is the same DTC displayed?
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Yes
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Replace the BCM, then go to the next step.
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No
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Go to Step 10.
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9
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VERIFY THAT REPAIRS HAVE BEEN COMPLETED
• Always reconnect all disconnected connectors.
• Connect the negative battery cable.
• Clear the DTC for the electrical supply unit (ESU) using the M-MDS.
• Retrieve the electrical supply unit (ESU) DTCs using the M-MDS.
• Is the same DTC displayed?
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Yes
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Repeat the inspection from Step 1.
• If the malfunction recurs, replace the electrical supply unit (ESU).
Go to the next step.
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No
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Go to the next step.
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10
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VERIFY IF OTHER DTCs DISPLAYED
• Are any other DTCs displayed?
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Yes
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Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
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No
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DTC troubleshooting completed.
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