Diagnostic Routine D

Diagnostic Routine D

Diagnostic Overview

The Power Liftgate Reverses During a Power Close Operation

Normal Operations and Fault Conditions

When the power liftgate moves in the close direction, the LTM (Liftgate/Trunk Module) monitors the pinch strip switches and motor position sensor for obstacle detection. If the LTM (Liftgate/Trunk Module) detects an obstacle, it reverses the power liftgate. The LTM (Liftgate/Trunk Module) also monitors the power liftgate latch status once the liftgate closes to a secondary latch position. If the liftgate is unable to obtain a primary latch position, the LTM (Liftgate/Trunk Module) aborts the power close.

DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Liftgate alignment

- Liftgate striker alignment

- Mechanical binding

Pinpoint Test

1. CHECK THE MANUAL OPERATION OF THE LIFTGATE

1. Turn the power liftgate off (disable) from the message center.

2. While manually opening and closing the liftgate, check the liftgate for:

- liftgate/wedge alignment
- strut operation (struts should push liftgate open when beyond half open)
- power liftgate latch (should latch completely)

Does the liftgate open and close correctly?








2. CHECK THE LIFTGATE POSITION SENSOR (OPT_SEN_1) AND (OPT_SEN_2) PIDs (Parameter Identifications)

1. Ignition ON.

2. Open the liftgate to the full open position.

3. Using the scan tool, view LTM (Liftgate/Trunk Module) PIDs (Parameter Identifications).

4. Monitor the LTM (Liftgate/Trunk Module) PIDs (Parameter Identifications) OPT_SEN_1 and OPT_SEN_2 while slowly closing the liftgate.

Do both of the PID (Parameter Identification) values alternate from ACTIVE to INACTIVE while the liftgate is moving?








3. CHECK THE DETENT AND FORKBOLT SWITCH PIDs (Parameter Identifications)

1. Using the scan tool, view the LTM (Liftgate/Trunk Module) PIDs (Parameter Identifications).

2. Operate the liftgate manually while monitoring the LTM (Liftgate/Trunk Module) PIDs (Parameter Identifications):

- Detent Switch Status (DETENTSW)
- Forkbolt Switch Status (FORKBLT_S)
- Forkbolt Secondary Switch (FKSWSEC)

3. NOTE: The liftgate is in the primary position when the liftgate is in the full closed position. The liftgate is in the unlatch position when the liftgate is open and completely out of the striker.

NOTE: If detent switch is active in the fully unlatched position, manually attempt to rotate the forkbolt towards the latched position.
Begin with the liftgate in the open position, then slowly close the liftgate into each of the latch positions specified.





Do the switch states agree with the table?








4. CHECK FOR CORRECT LTM (Liftgate/Trunk Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect all LTM (Liftgate/Trunk Module) connectors.

3. Repair:

- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

4. Reconnect all the LTM (Liftgate/Trunk Module) connectors. Make sure they seat and latch correctly.

5. Operate the system and determine if the concern is still present.

Is the concern still present?