DTC B144D-29: Error Signal Received From Power Liftgate (PLG) Drive Unit (LH) (BCM): Outline

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DTC B144D:29 (BCM) DETECTION CONDITION AND POSSIBLE CAUSE

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
Courtesy of MAZDA MOTORS CORP.