B1956
B1956 - Power Liftgate Latch Release Excessive Time
For a complete wiring diagram, refer to
• When Monitored: Whenever the power liftgate is performing a releasing operation.
• Set Condition: The latch motor should perform its operation within 4 seconds. When it takes longer for the release operation, this code will set.
Test Step 1 - DTC Present
• If there are any other power liftgate DTCs present, repair them before proceeding with this test.
• Ensure the battery is fully charged and serviceable before proceeding.
• Ensure the liftgate is closed and with the scan tool, run the "latch home position test" before proceeding to ensure the latch is positioned correctly.
• 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 B1956 - Power Liftgate Latch Release - Excessive Time?
Yes
• Go to Test Step 2
No
• Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for an intermittent condition. Operate the liftgate several times and check for any binding or other obstructions.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
Test Step 2 - Binding Liftgate
• Examine the liftgate for proper alignment, worn or binding hinges, weak liftgate prop assembly, loose/hard weatherstrip, and track assembly for wear or anything that would cause an obstruction to proper operation.
• If necessary manually operate the power liftgate on a known good vehicle and notice the effort needed to open and close for comparison.
• Especially notice the effort needed to unlatch and close the liftgate.
Were there any mechanical problems found?
Yes
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
No
• Go to Test Step 3
Test Step 3 - Check the Liftgate Latch Cinch Driver Circuit for an Open Or High Resistance
• Turn the ignition OFF.
• Disconnect the power liftgate module C2 and C3 harness connectors.
• Check the connectors for damage, corrosion, or pushed out pins. Repair any problems as necessary.
• Reconnect the PLG C3 harness connector.
• Disconnect the power liftgate latch harness connector.
• Measure the resistance of the liftgate latch cinch driver circuit between the power liftgate module C2 harness connector and the power liftgate latch harness connector.
• Wiggle the harness and check for an intermittent open condition.
Is the resistance less than 5.0 ohms?
Yes
• Go to Test Step 4
No
• Repair the liftgate latch cinch driver circuit for high resistance.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
Test Step 4 - Check the Liftgate Latch Release Driver Circuit for an Open Or High Resistance
• Measure the resistance of the liftgate latch release driver circuit between the power liftgate module C2 harness connector and the power liftgate latch harness connector.
• Wiggle the harness and check for an intermittent open condition.
Is the resistance less than 5.0 ohms?
Yes
• Go to Test Step 5
No
• Repair the liftgate latch release driver circuit for an open or high resistance.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
Test Step 5 - Check the Logic Ground Wire for an Open Or High Resistance
• Measure the resistance of the logic ground circuit between the PLG C2 harness connector and the PLG latch harness connector.
• Wiggle the harness and check for an intermittent short condition.
Is the resistance less than 5.0 ohms?
No
• Repair the logic ground circuit for an open or high resistance.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
Yes
• Go to Test Step 6
Test Step 6 - Check the Liftgate Ajar Switch Sense Circuit for an Open Or High Resistance
• Measure the resistance of the liftgate ajar switch sense circuit between the power liftgate latch C2 harness connector and the power liftgate latch connector.
• Wiggle the harness and check for an intermittent open condition.
Is the resistance less than 5.0 ohms?
No
• Repair the liftgate ajar switch sense circuit for an open or high resistance.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
Yes
• Replace the power liftgate latch.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior