Diagnostic Procedure

DTC B1142-13; IGNITION SWITCH STATUS MISMATCH - DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	INSPECT BCM CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) 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?	Yes	Go to the next step.
1		No	Repair or replace the connector, then go to Step 9.
2	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?	Yes	Go to the next step.
2		No	Repair or replace the connector, then go to Step 9.
3	VERIFY BCM POWER SUPPLY (IG1) VOLTAGE Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) Switch the ignition ON (engine off or on). Measure the voltage at the BCM terminal 3O (wiring harness-side). Is the voltage B+?	Yes	Go to Step 8.
3		No	Inspect the METER1 10 A fuse. If the fuse is blown: Refer to the wiring diagram and verify whether or not there is a common connector between METER1 10 A fuse and BCM terminal 3O. 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. Replace the fuse. If the fuse is damaged: Replace the fuse. If the fuse is normal: Refer to the wiring diagram and verify whether or not there is a common connector between IG1 relay and BCM terminal 3O. 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.
4	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+?	Yes	Go to Step 8.
4		No	Inspect the METER1 10 A fuse. If the fuse is blown: Refer to the wiring diagram and verify whether or not there is a common connector between METER1 10 A fuse and electrical supply unit (ESU) terminal 1H. 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. Replace the fuse. If the fuse is damaged: Replace the fuse. If the fuse is normal: Refer to the wiring diagram and verify whether or not there is a common connector between IG1 relay and electrical supply unit (ESU) terminal 1H. 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.
5	INSPECT LIN COMMUNICATION CIRCUIT BETWEEN BCM AND ELECTRICAL SUPPLY UNIT (ESU) FOR SHORT TO GROUND Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) 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?	Yes	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.
5		No	Go to the next step.
6	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. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) Switch the ignition ON (engine off or on). Measure the voltage at the BCM terminal 2Y (wiring harness-side). Is the voltage 0 V?	Yes	Go to the next step.
6		No	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.
7	INSPECT LIN COMMUNICATION CIRCUIT BETWEEN BCM AND ELECTRICAL SUPPLY UNIT (ESU) FOR OPEN CIRCUIT Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) 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?	Yes	Go to the next step.
7		No	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.
8	VERIFY IF MALFUNCTIONING LOCATION IS BCM DEPENDING ON REPEATABILITY Always reconnect all disconnected connectors. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) Clear the DTC for the electrical supply unit (ESU) using the M-MDS. (See CLEARING DTC [ELECTRICAL SUPPLY UNIT (ESU)] .) Retrieve the electrical supply unit (ESU) DTCs using the M-MDS. (See DTC INSPECTION [ELECTRICAL SUPPLY UNIT (ESU)] .) Is the same DTC displayed?	Yes	Replace the BCM, then go to the next step. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION .)
8		No	Go to Step 10.
9	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Always reconnect all disconnected connectors. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .) Clear the DTC for the electrical supply unit (ESU) using the M-MDS. (See CLEARING DTC [ELECTRICAL SUPPLY UNIT (ESU)] .) Retrieve the electrical supply unit (ESU) DTCs using the M-MDS. (See DTC INSPECTION [ELECTRICAL SUPPLY UNIT (ESU)] .) Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the electrical supply unit (ESU). (See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION .) Go to the next step.
9		No	Go to the next step.
10	VERIFY IF OTHER DTCs DISPLAYED Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [ELECTRICAL SUPPLY UNIT (ESU)] .)
10		No	DTC troubleshooting completed.