B1956-POWER LIFTGATE LATCH RELEASE - EXCESSIVE TIME
For a complete wiring diagram Refer to Section 8W
- 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.
| Possible Causes |
| BINDING LIFTGATE |
| LOW BATTERY VOLTAGE |
| LATCH NOT IN HOME POSITION |
| (Q84) LIFTGATE LATCH CINCH DRIVER CIRCUIT OPEN OR HIGH RESISTANCE |
| (Q85) LIFTGATE LATCH RELEASE DRIVER CIRCUIT OPEN OR HIGH RESISTANCE |
| (G78) LIFTGATE SWITCH SENSE CIRCUIT OPEN OR HIGH RESISTANCE |
| (Q901) LOGIC GROUND CIRCUIT OPEN OR HIGH RESISTANCE |
| LATCH ASSEMBLY |
Diagnostic Test
1. DTC PRESENTNOTE: If there are any other Power Liftgate DTCs present, repair them before proceeding with this test.
NOTE: 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 To2
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 BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
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
- Refer to Service information for the related symptom(s).
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Go To3
3. CHECK THE (Q84) 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 Power Liftgate Module C3 harness connector.
Disconnect the Power Liftgate Latch harness connector.
Measure the resistance of the (Q84) 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 below 5.0 ohms?
Yes
- Go To4
No
- Repair the (Q84) Liftgate Latch Cinch Driver circuit for high resistance.
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
4. CHECK THE (Q85) LIFTGATE LATCH RELEASE DRIVER CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
Measure the resistance of the (Q85) 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 below 5.0 ohms?
Yes
- Go To5
No
- Repair the (Q85) Liftgate Latch Release Driver circuit for an open or high resistance.
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
5. CHECK THE (Q901) LOGIC GROUND WIRE FOR AN OPEN OR HIGH RESISTANCE
Measure the resistance of the (Q901) Logic Ground circuit between the Power Liftgate Module C2 harness connector and the Power Liftgate Latch harness connector.
Wiggle the harness and check for an intermittent short condition.
Is the resistance below 5.0 ohms?
No
- Repair the (Q901) Logic Ground circuit for an open or high resistance.
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
Yes
- Go To 6
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
6. CHECK THE (G78) LIFTGATE AJAR SWITCH SENSE CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
Measure the resistance of the (G78) Liftgate Ajar Switch Sense circuit between the Power Liftgate Latch C2 harness connector and the Power Liftgate Latch harness connector.
Wiggle the harness and check for an intermittent open condition.
Is the resistance below 5.0 ohms?
No
- Repair the (G78) Liftgate Ajar Switch Sense circuit for an open or high resistance.
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING).
Yes
- Replace the Power Liftgate Latch in accordance with the service information.
- Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).