LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2021 >> Envision Preferred, AWD >> Repair and Diagnosis >> Body & Frame >> Body, Cab Control Systems >> Vehicle Access System >> Diagnostic Information and Procedures >> Power Liftgate Malfunction >> Circuit/System Verification

Circuit/System Verification

  1. Ignition ON.
  2. Liftgate Closed, verify the scan tool Rear Gate Latch Unlatch Switch, Rear Gate Latch Primary Switch, and Rear Gate Latch Neutral Switch parameters are as listed below:
    • Rear Gate Latch Unlatch Switch parameter Inactive
    • Rear Gate Latch Primary Switch parameter Inactive
    • Rear Gate Latch Neutral Switch parameter Inactive
    • Go to next step: If the parameters are as listed 
  3. Verify the A23C Liftgate Latch will activate and release the liftgate when pressing the appropriate button on the keyless entry transmitter twice
    • Go to next step: If the A23C Liftgate Latch does activate 
  4. Raise the liftgate to the fully open position, verify the scan tool parameter Rear Gate Travel is greater than 70%
    • Go to next step: If greater than the specified value 
  5. Liftgate Open, verify the scan tool Rear Gate Anti-pinch Sensor Raw Voltage parameter is between 3 V-3.5 V.
    • Go to next step: If between 3 V-3.5 V 
  6. Liftgate Open, verify the scan tool Rear Gate Latch Unlatch Switch, Rear Gate Latch Primary Switch, and Rear Gate Latch Neutral Switch parameters are as listed below:
    • Rear Gate Latch Unlatch Switch Status parameter Active
    • Rear Gate Latch Primary Switch Status parameter Active
    • Rear Gate Latch Neutral Switch Status parameter Inactive
    • Go to next step: If the parameters are as listed 
  7. Liftgate closed and latched, verify the A23C Liftgate Latch will activate and release the liftgate when pressing the E7AC Rear License Plate Lamp Module.
    • If the liftgate does not release when pressing the E7AC Rear License Plate Lamp Module 

      Refer to Circuit/System Testing - Test 1

    • Go to next step: If the liftgate does release when pressing the E7AC Rear License Plate Lamp Module 
  8. Verify the scan tool Rear Gate Close Switch parameter changes between Active and Inactive when pressing the B70 Liftgate Close Switch.
    • If the parameter does not change 

      Refer to Circuit/System Testing - Test 2

    • Go to next step: If the parameter changes 
  9. Verify the liftgate will perform the power open and power close functions when pressing the B70 Liftgate Close Switch.
    • Go to next step: If the liftgate does power open and close 
  10. Rotate the S45B Liftgate Control Switch - Interior to the Max setting
  11. Operate the component: S45B Liftgate Control Switch - Interior - Pressed

    Verify the Power Liftgate (TB5) performs the power open or the power close function

    • If the Power Liftgate (TB5) does not perform the power open or the power close function 

      Refer to Circuit/System Testing - Test 3

    • Go to next step: If the Power Liftgate (TB5) performs the power open or the power close function 
  12. Rotate the S45B Liftgate Control Switch - Interior to the Off setting

    Operate the component: E7AC Rear License Plate Lamp Module - Pressed

    Verify the Power Liftgate (TB5) power open function has been disabled

    • If the Power Liftgate (TB5) activates and performs the power open function 

      Refer to Circuit/System Testing - Test 4

    • Go to next step: If the Power Liftgate (TB5) power open function has been disabled 
  13. Rotate the S45B Liftgate Control Switch - Interior to the 3/4 setting

    Operate the component: E7AC Rear License Plate Lamp Module - Pressed

    Verify the Power Liftgate (TB5) power opens and stops at the garage mode position

    • If the Power Liftgate (TB5) only opens and stops at the full open position 

      Refer to Circuit/System Testing - Test 4

    • Go to next step: If the Power Liftgate (TB5) power opens and stops at the garage mode position 
  14. A fault is not currently present and may be an intermittent condition