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DTC B144D:29 [BODY CONTROL MODULE (BCM)]

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Outline

System malfunction location	Error signal received from power liftgate (PLG) drive unit (LH)
Detection condition	•  The power liftgate (PLG) control module detects any of the following conditions. ―  The power liftgate (PLG) control module detects that a pulse signal from the power liftgate (PLG) drive unit (LH) is stuck at HI or LO for a continuous 1 s or more. ―  The power liftgate (PLG) control module detects that a power supply voltage error of the power liftgate (PLG) drive unit rotation sensor (LH) continues for a certain period of time while the power liftgate (PLG) drive unit motor is operating. ―  The power liftgate (PLG) control module detects that there is no change in the power liftgate (PLG) drive unit rotation sensor (LH) signal and the difference between the rotation speed of the power liftgate (PLG) drive unit motors (LH) and (RH) exceeds 10 times.
Fail-safe	•  Stops the power liftgate (PLG) system operation.
Possible cause	•  Power liftgate (PLG) drive unit (LH) connector or terminal malfunction •  Power liftgate (PLG) control module connector or terminal malfunction •  Short to ground in power liftgate (PLG) drive unit (LH) signal circuit •  Short to power supply in power liftgate (PLG) drive unit (LH) signal circuit •  Open circuit in power liftgate (PLG) drive unit (LH) signal circuit •  Power liftgate (PLG) drive unit (LH) malfunction •  Power liftgate (PLG) control module malfunction •  Body control module (BCM) malfunction

Diagnostic Procedure

Step	Inspection	Results	Action
1	INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
2	INSPECT POWER LIFTGATE (PLG) CONTROL MODULE CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
3	INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) SIGNAL CIRCUIT FOR SHORT TO GROUND •  Inspect the applicable circuit for a short to ground. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY •  Inspect the applicable circuit for a short to power supply. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) SIGNAL CIRCUIT FOR OPEN CIRCUIT •  Inspect the applicable circuit for an open circuit. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) FOR MALFUNCTION DEPENDING ON REPEATABILITY •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Switch the ignition ON (engine off or on) and wait for 1 s or more. •  Operate the power liftgate (PLG) system. •  Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) •  Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, replace the power liftgate (PLG) drive unit (LH), then go to the next step. (See POWER LIFTGATE (PLG) DRIVE UNIT REMOVAL/INSTALLATION.)
		No	Go to repair completion verification 2.
7	INSPECT POWER LIFTGATE (PLG) CONTROL MODULE FOR MALFUNCTION DEPENDING ON REPEATABILITY •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Switch the ignition ON (engine off or on) and wait for 1 s or more. •  Operate the power liftgate (PLG) system. •  Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) •  Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, replace the power liftgate (PLG) control module and perform the repair completion verification. (See POWER LIFTGATE (PLG) CONTROL MODULE REMOVAL/INSTALLATION.)
		No	Go to repair completion verification 2.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Switch the ignition ON (engine off or on) and wait for 1 s or more. •  Operate the power liftgate (PLG) system. •  Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) •  Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. •  If the malfunction recurs, replace the body control module (BCM), then go to the next step. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)
		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTC IS DISPLAYED •  Perform the DTC inspection. (See DTC INSPECTION.) •  Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
		No	DTC troubleshooting completed.