Pinpoint Test B: Luggage Compartment Lid Latch Opens, Lid Motor Inoperative
Luggage Compartment Lid
Pinpoint Tests
Pinpoint Test B: Luggage Compartment Lid Latch Opens, Lid Motor Inoperative
Refer to Wiring Diagram Set 113, Luggage Compartment for schematic and connector information. Diagrams By Number
Normal Operation
The Liftgate/Trunk Module (LTM) receives voltage from the Battery Junction Box (BJB) through circuit 1190 (YE/BK) and grounds through circuit 57 (BK). The LTM receives a voltage signal from the Driver Door Module (DDM) when either the button on the driver door trim panel, the Remote Keyless Entry (RKE) keypad or the RKE transmitter is pressed (twice on the RKE transmitter). The luggage compartment lid latch release switch releases the lid latch when voltage is supplied to circuit 486 (BN/WH). The LTM supplies voltage to the luggage compartment lid release solenoid on circuit 605 (RD) releasing the luggage compartment lid, and to the lid motor through circuit 1600 (TN/RD) and grounds 1602 (WH/OG) on the luggage compartment lid motor to engage the clutch through 1609 (LG/YE) and move the lid to the full-open position. To close the luggage compartment lid, the motor is grounded on circuit 1600 (TN/RD) through the LTM and the clutch is grounded to circuits 1610 (WH/LB) and 57 (BK).
Optical sensors located on circuits 1617 (WH/LG) and 1618 (WH/BK) within the lid motor are monitored by the LTM to determine when to turn off power and which circuits should be powered or grounded to the lid motor. The sensors receive voltage on circuit 1615 (WH/YE) and ground on circuit 1616 (OG/LG).
When one of the buttons is pressed with the lid open, the DDM sends a signal to the LTM which supplies voltage to 1602 (WH/OG) and grounds circuit 1600 (TN/RD) to the lid motor and lowers the lid until the latch closes.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Luggage compartment lid motor
- Luggage compartment latch switch
- LTM
PINPOINT TEST B: LUGGAGE COMPARTMENT LID LATCH OPENS, LID MOTOR INOPERATIVE
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use correct probe adapter(s) may damage the connector.
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B1 CHECK DTCs FOR THE LTM
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test - Liftgate/Trunk Module (LTM).
- Carry out the LTM on-demand self test.
- Are any LTM DTCs retrieved?
Yes
GO to the Liftgate/Trunk Module (LTM) DTC Chart. If referred here from the Liftgate/Trunk Module (LTM) DTC Chart, GO to B2. Diagnostic Trouble Code Tests and Associated Procedures
No
GO to B2.
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B2 VERIFY THE INTEGRITY OF THE LUGGAGE COMPARTMENT LID MOTOR
- Ignition OFF.
- Disconnect: LTM C4081b, C4081d.
- Connect a fused jumper wire between LTM C4081d-4, circuit 1190 (YE/BK), harness side and LTM C4081b-7, circuit 1600 (TN/RD), harness side. Then momentarily ground LTM C4081b-1, circuit 1602 (WH/OG). Switch voltage and ground on these pins to verify the lid motor operates in both directions.
- Does the lid motor operate in both directions?
Yes
GO to B5.
No
VERIFY BJB fuse 108 (40A) is OK. If OK, GO to B3. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation. Diagrams By Number
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B3 CHECK THE LID MOTOR CIRCUIT 1600 (TN/RD) FOR AN OPEN
- Disconnect: Luggage Compartment Lid Motor C4200.
- Measure the resistance between LTM C4081b-7, circuit 1600 (TN/RD), harness side and lid motor C4200-2, circuit 1600 (TN/RD), harness side; and between lid motor C4200-2, circuit 1600 (TN/RD), harness side and ground.
- Is the resistance less than 5 ohms between the LTM and the lid motor, and greater than 10,000 ohms between the lid motor and ground?
Yes
GO to B4.
No
REPAIR circuit 1600 (TN/RD). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B4 CHECK THE LID MOTOR CIRCUIT 1602 (WH/OG) FOR AN OPEN
- Measure the resistance between LTM C4081b-1, circuit 1602 (WH/OG), harness side and lid motor C4200-6, circuit 1602 (WH/OG), harness side; and between lid motor C4200-6, circuit 1602 (WH/OG), harness side and ground.
- Is the resistance less than 5 ohms between the LTM and the lid motor, and greater than 10,000 ohms between the lid motor and ground?
Yes
CHECK the jumper harness for opens, shorts to voltage and shorts to ground. If the harness is OK, INSTALL a new luggage compartment lid motor. REFER to Luggage Compartment Lid Motor Service and Repair.
CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation. If the harness is not OK, INSTALL a new luggage compartment lid motor assembly. REFER to Luggage Compartment Lid Motor Service and Repair. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
REPAIR circuit 1602 (WH/OG). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B5 CHECK THE CIRCUITS TO THE LID MOTOR
- Ignition OFF.
- Disconnect: LTM C4081c, Luggage Compartment Lid Motor C4200.
- Measure the resistance between LTM, harness side and lid motor, harness side using the following chart:
- Is the resistance less than 5 ohms between the LTM and the luggage compartment lid motor connector?
Yes
GO to B6.
No
REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B6 CHECK THE CIRCUITS TO THE LID MOTOR FOR A SHORT TO GROUND
- Measure the resistance between LTM C4081c, harness side and ground using the following chart:
- Is the resistance greater than 10,000 ohms between the LTM and ground?
Yes
GO to B7.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B7 INSTALL A KNOWN GOOD LUGGAGE COMPARTMENT LID MOTOR
- Install a known good luggage compartment lid motor.
- Does the system operate correctly?
Yes
INSTALL a new luggage compartment lid motor. REFER to Luggage Compartment Lid Motor Service and Repair. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to B8.
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B8 CHECK THE LUGGAGE COMPARTMENT LATCH SWITCH
- Disconnect: LTM C4081a.
- Close the luggage compartment lid latch. Due to the location of the LTM, close the latch with the lid open.
- Measure the resistance between LTM C4081a-4, circuit 486 (BN/WH), harness side and ground, then open the latch using either the key or the manual release cable.
- Is the resistance less than 5 ohms with the latch closed, and greater than 10,000 ohms with the latch open?
Yes
GO to B11.
No
GO to B9.
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B9 CHECK CIRCUIT 486 (BN/WH) FOR AN OPEN
- Disconnect: Luggage Compartment Lid Latch C430.
- Measure the resistance between LTM C4081a-4, circuit 486 (BN/WH), harness side and luggage compartment lid latch
C430-1, circuit 486 (BN/WH), harness side; and between LTM C4081a-4, circuit 486 (BN/WH), harness side and ground.
- Is the resistance less than 5 ohms between the module and latch connectors, and greater than 10,000 ohms between the module connector and ground?
Yes
GO to B10.
No
REPAIR circuit 486 (BN/WH). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B10 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Measure the resistance between luggage compartment lid latch C430-3, circuit 57 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new luggage compartment lid latch. REFER to Doors, Hood and Trunk &/or Locks. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
REPAIR circuit 57 (BK). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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B11 CHECK FOR CORRECT MODULE OPERATION
- Disconnect all the LTM connectors
- Check for:
- corrosion.
- pushed-out pins.
- Connect all the LTM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new LTM. REPEAT the self-test. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
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