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Diagnostic Procedure

DTC B144D:29 [POWER LIFTGATE (PLG) CONTROL MODULE] DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the negative battery terminal.

    (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)

  • Disconnect the power liftgate (PLG) drive unit (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.
No Repair or replace the connector, then go to Step 7.
2 INSPECT POWER LIFTGATE (PLG) CONTROL MODULE CONNECTOR CONDITION
  • Disconnect the power liftgate (PLG) control module 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.
No Repair or replace the connector, then go to Step 7.
3 INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) CIRCUIT FOR SHORT TO GROUND
  • Verify that the power liftgate (PLG) drive unit (LH) and power liftgate (PLG) control module connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Power liftgate (PLG) drive unit (LH) terminal D
    • Power liftgate (PLG) drive unit (LH) terminal B
  • Is there continuity?
 Yes Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Power liftgate (PLG) drive unit (LH) terminal D-Power liftgate (PLG) control module terminal 1J
  • Power liftgate (PLG) drive unit (LH) terminal B-Power liftgate (PLG) control module 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.

Go to Step 7.
No Go to the next step.
4 INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the power liftgate (PLG) drive unit (LH) and power liftgate (PLG) control module 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):
    • Power liftgate (PLG) drive unit (LH) terminal D
    • Power liftgate (PLG) drive unit (LH) terminal B
  • Is the voltage 0 V?
 Yes Go to the next step.
No Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Power liftgate (PLG) drive unit (LH) terminal D-Power liftgate (PLG) control module terminal 1J
  • Power liftgate (PLG) drive unit (LH) terminal B-Power liftgate (PLG) control module 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 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 POWER LIFTGATE (PLG) DRIVE UNIT (LH) CIRCUIT FOR OPEN CIRCUIT
  • Switch the ignition off.
  • Disconnect the negative battery terminal.

    (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)

  • Verify that the power liftgate (PLG) drive unit (LH) and power liftgate (PLG) control module connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side):
  • Power liftgate (PLG) drive unit (LH) terminal D-Power liftgate (PLG) control module terminal 1J
  • Power liftgate (PLG) drive unit (LH) terminal B-Power liftgate (PLG) control module terminal 1H
  • Is there continuity?
 Yes Go to the next step.
No Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Power liftgate (PLG) drive unit (LH) terminal D-Power liftgate (PLG) control module terminal 1J
  • Power liftgate (PLG) drive unit (LH) terminal B-Power liftgate (PLG) control module 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 7.
6 INSPECT POWER LIFTGATE (PLG) DRIVE UNIT (LH) Yes Go to the next step.
No Replace the power liftgate (PLG) drive unit (LH), then go to the next step.
(See POWER LIFTGATE (PLG) DRIVE UNIT REMOVAL/INSTALLATION .)
7 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
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 [POWER LIFTGATE (PLG) CONTROL MODULE] .)
No DTC troubleshooting completed.
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