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Circuit/System Testing

WARNING: This page is about a different car, the 2018 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

Test 1

    NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: S58A Rear Compartment Lid Unlatch Switch - Exterior
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 2 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 2 @ Component harness & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  4. Ignition - On/Vehicle - In Service Mode
  5. Verify the scan tool parameter: Trunk Lid/Liftgate Window Exterior Unlatch Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector: K9 Body Control Module
    3. Test for infinite resistance between the test points: Signal circuit terminal 1 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: K9 Body Control Module
    • Go to next step: If the specified state 
  6. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 1 & Ground circuit terminal 2
  7. Verify the scan tool parameter: Trunk Lid/Liftgate Window Exterior Unlatch Switch = Active
    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector: K9 Body Control Module
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 1 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for less than 2 ohms between the test points: Signal circuit terminal 1 @ Component harness & Terminal 15 X6 @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: K9 Body Control Module
    • Go to next step: If the specified state 
  8. Test or replace the component: S58A Rear Compartment Lid Unlatch Switch - Exterior

Test 2

    NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: S58B Rear Compartment Lid Unlatch Switch - Interior
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 2 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 2 @ Component harness & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  4. Ignition - On/Vehicle - In Service Mode
  5. Verify the scan tool parameter: Interior Liftgate/Liftgate Window Unlatch Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector: X6 @ K9 Body Control Module
    3. Test for infinite resistance between the test points: Signal circuit terminal 1 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: K9 Body Control Module
    • Go to next step: If the specified state 
  6. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 1 & Ground circuit terminal 2
  7. Verify the scan tool parameter: Interior Liftgate/Liftgate Window Unlatch Switch = Active
    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector: X6 @ K9 Body Control Module
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 1 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for less than 2 ohms between the test points: Signal circuit terminal 1 @ Component harness & Terminal 14 X6 @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: K9 Body Control Module
    • Go to next step: If the specified state 
  8. Test or replace the component: S58B Rear Compartment Lid Unlatch Switch - Interior

Test 3

    NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: M40 Rear Compartment Lid Latch
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 2 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 2 & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  4. Verify the fuse is not open: F16RA Fuse
    • If the fuse is open 
    1. Replace the component: F16RA Fuse
    2. Verify the fuse does not open.
      • If the fuse opens - Test or replace the component: X53A Fuse Block - Rear Body
      • If the fuse does not open, go to the next step.
    • Go to next step: If the fuse is not open 
  5. Connect a test lamp between the test points: Control circuit terminal 1 & Ground circuit terminal 2
  6. Ignition - On/Vehicle - In Service Mode
  7. Perform the scan tool control function: Trunk Lid Unlatch Command - Unlatch

    Verify the test lamp does not turn On and Off.

    • If the test lamp turns On and Off 

      Test or replace the component: M40 Rear Compartment Lid Latch

    • Go to next step: If the test lamp does not turn On and Off 
  8. Ignition/Vehicle - Off
  9. Connect the electrical connector: M40 Rear Compartment Lid Latch
  10. Disconnect the electrical connector: X3 @ X53A Fuse Block - Rear Body
  11. Ignition - On/Vehicle - In Service Mode
  12. Momentarily connect a 10 A fused jumper wire between the test points: Control circuit terminal 8 X3 & B+

    Verify the component turns On and Off when connecting and disconnecting the jumper wire: M40 Rear Compartment Lid Latch

    • If the component does not turn On and Off 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector: M40 Rear Compartment Lid Latch
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Control circuit terminal 1 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Control circuit terminal 1 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Control circuit terminal 1 @ Component harness & Terminal 8 X3 @ Fuse Block Harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Test or replace the component: M40 Rear Compartment Lid Latch
    • Go to next step: If the component turns On and Off 
  13. Ignition/Vehicle & All vehicle systems - Off
  14. Verify the fuse is not open: F16RA Fuse
    • If the fuse is open 

      Test or replace the component: X53A Fuse Block - Rear Body

    • Go to next step: If the fuse is not open 
  15. Test for less than 10 ohms between the test points: Ground circuit terminal 12 X3 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 12 X3 & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  16. Connect the electrical connector: X3 @ X53A Fuse Block - Rear Body
  17. Disconnect the electrical connector: X5 @ K9 Body Control Module
  18. Ignition - On/Vehicle - In Service Mode
  19. Momentarily connect a 3 A fused jumper wire between the test points: Control circuit terminal 11 X5 & B+

    Verify the component turns On and Off when connecting and disconnecting the jumper wire: M40 Rear Compartment Lid Latch

    • If the component does not turn On and Off 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector: X3 @ X53A Fuse Block - Rear Body
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Control circuit terminal 11 X5 @ Control module harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Control circuit terminal 11 X5 @ Control module harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Control circuit terminal 11 X5 @ Control module harness & Terminal 21 X3 @ Fuse Block Harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Test or replace the component: X53A Fuse Block - Rear Body
    • Go to next step: If the component turns On and Off 
  20. Replace the component: K9 Body Control Module
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