DTC U0140:00 [ELECTRICAL SUPPLY UNIT (ESU)]

id0902ff063100

Description

Communication error with BCM

Detection condition

•  Electrical supply unit (ESU) could not receive the CAN signal from the BCM for 2 s or more with the ignition switched ON (engine off or on).

Fail-safe

Exterior lighting system

•  When the ignition is switched ON (engine off or on), the headlights LO, TNS, and panel light turn on and other exterior light controls are stopped.

Interior light control system

•  Turn the interior light off.

Rear wiper system

•  Stop the rear wiper.

Possible cause

•  BCM connector or terminal malfunction

•  Electrical supply unit (ESU) connector or terminal 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

Description	Communication error with BCM
Detection condition	• Electrical supply unit (ESU) could not receive the CAN signal from the BCM for 2 s or more with the ignition switched ON (engine off or on).
Fail-safe	Exterior lighting system • When the ignition is switched ON (engine off or on), the headlights LO, TNS, and panel light turn on and other exterior light controls are stopped. Interior light control system • Turn the interior light off. Rear wiper system • Stop the rear wiper.
Possible cause	• BCM connector or terminal malfunction • Electrical supply unit (ESU) connector or terminal 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

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 7.
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 7.
3	INSPECT LIN COMMUNICATION CIRCUIT BETWEEN BCM AND ELECTRICAL SUPPLY UNIT (ESU) FOR SHORT TO GROUND • 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 7.
3		No	Go to the next step.
4	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.
4		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 7.
5	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.
5		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 7.
6	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)].) • Switch the ignition ON (engine off or on) and wait for 2 s or more. • 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.)
6		No	Go to Step 8.
7	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)].) • Switch the ignition ON (engine off or on) and wait for 2 s or more. • 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.
7		No	Go to the next step.
8	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)].)
8		No	DTC troubleshooting completed.