B1977 - Power Liftgate Open Direction Sector Switch Performance: Notes
For a complete wiring diagram, refer to appropriate Wiring Diagram
- >>When Monitored:<< Whenever the power liftgate is performing a power open operation.
- >>Set Condition:<< The sector switch is unstable prior to an opening operation.
| Possible Causes |
|---|
| BINDING LIFTGATE |
| LATCH NOT IN HOME POSITION |
| Q901 LOGIC GROUND CIRCUIT OPEN |
| Q79 SECTOR SWITCH SENSE CIRCUIT OPEN |
| Q79 SECTOR SWITCH SENSE CIRCUIT SHORT TO VOLTAGE |
| Q79 SECTOR SWITCH SENSE CIRCUIT SHORT TO GROUND |
| POWER LIFTGATE LATCH |
| POWER LIFTGATE MODULE |
Theory of Operation
The sector switch is essentially a park switch for the latch. When the latch is running a cinch or release operation, the switch is closed. After the cinch or release is complete, the PLGM will reverse direction of the latch until the switch is open.
Test Step 1 - Check for DTCs
NOTE:
This DTC will only set during the power open operation after the four second time out. This may make it difficult to reproduce.
- With the scan tool, record and erase DTCs.
- Turn the ignition OFF, wait 10 seconds, then turn the ignition ON.
- Operate the power liftgate several times if possible.
- With the scan tool, read Active DTCs.
Does the scan tool display B1977 - Power Liftgate Open Operation Sector Switch Performance?
Yes
No
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for an intermittent condition. Operate the door several times and check for any binding or other obstructions.
- Perform the Body Verification Test. Refer to BODY VERIFICATION TEST .