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Home >> Buick >> 2017 >> Envision Essence, FWD >> Repair and Diagnosis >> Accessories & Equipment >> Collision/Avoidance >> Object Detection System And Pedestrian Protection System >> Diagnostic Information and Procedures >> Lane Keep Assist System Malfunction >> Circuit/System Testing
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Circuit/System Testing

lane keep assist Switch Circuit Malfunction (without UGN)

  1. Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 7 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the ground circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Ignition ON.
  4. Verify the scan tool Lane Keep Assist switch parameter is Off.
    • If not Off 
    1. Ignition OFF, disconnect the harness connector at the K109 Frontview Camera Module.
    2. Test for infinite resistance between the S48A Multifunction Switch - Instrument Panel signal circuit terminal 4 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K109 Frontview Camera Module.
    • If Off 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 4 and ground.
  6. Verify the scan tool lane keep assist Switch parameter is On.
    • If not On 
    1. Ignition OFF, disconnect the harness connector at the K109 Frontview Camera Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K109 Frontview Camera Module.
    • If On 
  7. Test or replace the S48A Multifunction Switch - Instrument Panel.

Lane Keep Assist Switch Indicator Circuit Malfunction (without UGN)

  1. Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel, ignition ON.
    2. NOTE:

    Verify interior lighting dimming is turned all the way up.

  2. Test for 6.2 - 10.9 V between the dimming control circuit terminal 9 and ground terminal 13.
    • If less than 6.2 V 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
    • If greater than 10.9 V 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit and ground.
    • If between 6.2 - 10.9 V 
  3. Connect a test lamp between the control circuit terminal 9 and B+.
  4. Verify the test lamp turns ON and OFF when Commanding the lane keep assist Indicator ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the harness connector at the K109 Frontview Camera Module, ignition ON.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Ignition OFF.
    4. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S48A Multifunction Switch - Instrument Panel.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the harness connector at the K109 Frontview Camera Module.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K109 Frontview Camera Module.
    • If the test lamp turns ON and OFF 
  5. Test or replace the S48A Multifunction Switch - Instrument Panel.

Lane Keep Assist Switch Circuit Malfunction (with UGN)

  1. Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 7 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the ground circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Ignition ON.
  4. Verify the scan tool lane keep assist Switch parameter is Off.
    • If not Off 
    1. Ignition OFF, disconnect the harness connector at the K124 Active Safety Control Module.
    2. Test for infinite resistance between the S48A Multifunction Switch - Instrument Panel signal circuit terminal 4 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K124 Active Safety Control Module.
    • If Off 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 4 and ground.
  6. Verify the scan tool lane keep assist Switch parameter is On.
    • If not On 
    1. Ignition OFF, disconnect the harness connector at the K124 Active Safety Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K124 Active Safety Control Module.
    • If On 
  7. Test or replace the S48A Multifunction Switch - Instrument Panel.

Lane Keep Assist Switch Indicator Circuit Malfunction (with UGN)

  1. Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel.
    2. NOTE:

    Verify interior lighting dimming is turned all the way up.

  2. Ignition ON, test for 6.2 - 10.9 V between the dimming control circuit terminal 13 and ground.
    • If less than 6.2 V 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
    • If greater than 10.9 V 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit and ground.
    • If between 6.2 - 10.9 V 
  3. Connect a test lamp between the control circuit terminal 9 and B+.
  4. Verify the test lamp turns ON and OFF when Commanding the lane keep assist Indicator ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the harness connector at the K124 Active Safety Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Ignition OFF.
    4. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S48A Multifunction Switch - Instrument Panel.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the harness connector at the K124 Active Safety Control Module.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K124 Active Safety Control Module.
    • If the test lamp turns ON and OFF 
  5. Test or replace the S48A Multifunction Switch - Instrument Panel.
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