DTC B1B40:14 [PARKING ASSIST UNIT]

id0902q6240800

Description	Front corner ultrasonic sensor (LH) circuit malfunction
Detection condition	• The parking assist unit detected a front corner ultrasonic sensor (LH) circuit malfunction with the ignition switched ON (engine off or on).
Fail-safe	Not applicable
Possible cause	• Front bumper external appearance damage or incorrect front bumper installation ? Abnormal front bumper installation angle • Front corner ultrasonic sensor (LH) malfunction • Front corner ultrasonic sensor (LH) connector or terminal malfunction • Parking assist unit connector or terminal malfunction • Short to ground in wiring harness between the following terminals: ? Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J ? Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I • Short to power supply in wiring harness between the following terminals: ? Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J ? Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I • Open circuit in wiring harness between the following terminals: ? Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J ? Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I • Parking assist unit malfunction

Diagnostic Procedure

Step	Inspection		Action
1	VERIFY OTHER PARKING ASSIST UNIT DTCs • Clear the DTC for the parking assist unit using the M-MDS. (See CLEARING DTC [PARKING ASSIST UNIT].) • Retrieve the parking assist unit DTCs using the M-MDS. (See DTC INSPECTION [PARKING ASSIST UNIT].) • Is DTC U3000:49 displayed?	Yes	Replace the parking assist unit, then go to Step 9. (See PARKING ASSIST UNIT REMOVAL/INSTALLATION.)
1		No	Go to the next step.
2	VERIFY FRONT BUMPER EXTERNAL APPEARANCE AND INSTALLATION CONDITION • Verify that the front bumper external appearance and installation condition. • Are the front bumper external appearance and installation condition normal?	Yes	Go to the next step.
2		No	Repair or replace the front bumper, then go to Step 9. (See FRONT BUMPER REMOVAL.) (See FRONT BUMPER INSTALLATION.)
3	PERFORM DTC INSPECTION AND VERIFY FRONT CORNER ULTRASONIC SENSOR (LH) MALFUNCTION Note • If the left sensor is switched with the right sensor and the output DTC changes, there is a malfunction in the front corner ultrasonic sensor (LH) before the positions were switched. • Switch the ignition off. • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION.) • Disconnect the front corner ultrasonic sensor (RH) connector and the front corner ultrasonic sensor (LH) connector. • Switch the front corner ultrasonic sensor (RH) with the front corner ultrasonic sensor (LH). (See FRONT ULTRASONIC SENSOR REMOVAL/INSTALLATION.) • Always reconnect all disconnected connectors. • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION.) • Clear the DTC for the parking assist unit using the M-MDS. (See CLEARING DTC [PARKING ASSIST UNIT].) • Switch the ignition ON (engine off or on) and wait for 5 s or more. • Retrieve the parking assist unit DTCs using the M-MDS. (See DTC INSPECTION [PARKING ASSIST UNIT].) • Is DTC B1B36:14 or B1B40:14 displayed?	Yes	If DTC B1B40:14 is displayed: • Go to the next step. If DTC B1B36:14 is displayed: • Replace the front corner ultrasonic sensor (RH) (front corner ultrasonic sensor (LH) before switching), then go to Step 9. (See FRONT ULTRASONIC SENSOR REMOVAL/INSTALLATION.)
3		No	Return the switched sensor to its original position, and perform the DTC inspection for the parking assist unit. (See FRONT ULTRASONIC SENSOR REMOVAL/INSTALLATION.) (See DTC INSPECTION [PARKING ASSIST UNIT].) If DTC B1B40:14 is displayed: • Go to the next step. If DTC B1B40:14 is not displayed: • Go to Step 10.
4	INSPECT FRONT CORNER ULTRASONIC SENSOR (LH) CONNECTOR CONDITION • Switch the ignition off. • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION.) • Disconnect the front corner ultrasonic sensor (LH) 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.
4		No	Repair or replace the connector, then go to Step 9.
5	INSPECT PARKING ASSIST UNIT CONNECTOR CONDITION • Disconnect the parking assist unit 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.
5		No	Repair or replace the connector, then go to Step 9.
6	INSPECT FRONT CORNER ULTRASONIC SENSOR (LH) CIRCUIT FOR SHORT TO GROUND • Verify that the front corner ultrasonic sensor (LH) and parking assist unit connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side) and body ground: ? Front corner ultrasonic sensor (LH) terminal A ? Front corner ultrasonic sensor (LH) terminal B • Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J • Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I 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.
6		No	Go to the next step.
7	INSPECT FRONT CORNER ULTRASONIC SENSOR (LH) CIRCUIT FOR SHORT TO POWER SUPPLY • Verify that the front corner ultrasonic sensor (LH) and parking assist unit connectors are disconnected. • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION.) • Switch the ignition ON (engine off or on). • Measure the voltage at the following terminals (wiring harness-side): ? Front corner ultrasonic sensor (LH) terminal A ? Front corner ultrasonic sensor (LH) terminal B • Is the voltage 0 V?	Yes	Go to the next step.
7		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J • Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I 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.
8	INSPECT FRONT CORNER ULTRASONIC SENSOR (LH) CIRCUIT FOR OPEN CIRCUIT • Switch the ignition off. • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION.) • Verify that the front corner ultrasonic sensor (LH) and parking assist unit connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side): ? Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J ? Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I • Is there continuity?	Yes	Go to the next step.
8		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Front corner ultrasonic sensor (LH) terminal A—Parking assist unit terminal J • Front corner ultrasonic sensor (LH) terminal B—Parking assist unit terminal I 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 the next step.
9	VERIFY THAT REPAIRS HAVE BEEN COMPLETED • Always reconnect all disconnected connectors. • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION.) • Clear the DTC for the parking assist unit using the M-MDS. (See CLEARING DTC [PARKING ASSIST UNIT].) • Retrieve the parking assist unit DTCs using the M-MDS. (See DTC INSPECTION [PARKING ASSIST UNIT].) • Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the parking assist unit. (See PARKING ASSIST UNIT 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 [PARKING ASSIST UNIT].)
10		No	DTC troubleshooting completed.