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Circuit/System Testing

Driver Door Lock Switch Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S13D Door Lock Switch-Driver. 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 4 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 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 Driver Door Lock Switch parameter is Inactive.
    • If not Inactive 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the signal circuit terminal 3 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
    3. Test for infinite resistance between the signal circuit terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K9 Body Control Module.
    • If Inactive 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the ground circuit terminal 4.
  6. Verify the scan tool Driver Door Lock Switch parameter is Unlock.
    • If not Unlock 
    1. Ignition OFF, remove the fused jumper wire, disconnect the harness connector at the K9 Body 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 K9 Body Control Module.
    • If Unlock 
  7. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 4.
  8. Verify the scan tool Driver Door Lock Switch parameter is Lock.
    • If not Lock 
    1. Ignition OFF, remove the fused jumper wire, disconnect the harness connector at the K9 Body 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 K9 Body Control Module.
    • If Lock 
  9. Test or replace the S13D Door Lock Switch-Driver.

Passenger Door Lock Switch Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S13P Door Lock Switch-Passenger. 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 4 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 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 Passenger Door Lock Switch parameter is Inactive.
    • If not Inactive 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the signal circuit terminal 3 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
    3. Test for infinite resistance between the signal circuit terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K9 Body Control Module.
    • If Inactive 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the ground circuit terminal 4.
  6. Verify the scan tool Passenger Door Lock Switch parameter is Unlock.
    • If not Unlock 
    1. Ignition OFF, remove the fused jumper wire, disconnect the harness connector at the K9 Body 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 K9 Body Control Module.
    • If Unlock 
  7. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 4.
  8. Verify the scan tool Passenger Door Lock Switch parameter is Lock.
    • If not Lock 
    1. Ignition OFF, remove the fused jumper wire, disconnect the harness connector at the K9 Body 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 K9 Body Control Module.
    • If Lock 
  9. Test or replace the S13P Door Lock Switch-Passenger.

Driver Door Lock Malfunction

  1. Ignition OFF, disconnect the X6 harness connector at the K9 Body Control Module, ignition ON.
  2. Test for less than 1 V between the control circuit terminal 1 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the A23D Door Latch Assembly - Driver, 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, connect the X6 harness connector at the K9 Body Control Module. Disconnect the harness connector at the A23D Door Latch Assembly-Driver, ignition ON.
    4. NOTE:

    Leaving the DMM connected between a control circuit and ground for greater than 20 s may cause the K9 Body Control Module to interpret the test as a system fault and will cause the voltage on the control circuit to drop to 0 V. If the voltage drops to 0 V, operate the door locks using the door lock switch to restore the voltage for testing.

  4. Test for greater than 3 V between the control circuit terminals listed below and ground:
    • Control circuit terminal 7
    • Control circuit terminal 8
    • If 3 V or less 
    1. Ignition OFF, disconnect the X6 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 on the circuit.
      • If infinite resistance.
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance on the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If greater than 3 V 
    5. NOTE:

    When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 00.00 V.

  5. Install a DMM between the control circuit terminal 7 and control circuit terminal 8. Set the DMM to capture DC voltage using the MIN MAX function. Turn off autorange and manually set the DMM range to 00.00 V.
  6. Lock and unlock the vehicle doors using the S13D Door Lock Switch-Driver.
  7. Verify the MAX voltage captured by the DMM is greater than 10 V.
    • If 10 V or less 

      Replace the K9 Body Control Module.

    • If greater than 10 V 
  8. Test or replace the A23D Door Latch Assembly-Driver.

Passenger Door Lock Malfunction

  1. Ignition OFF, disconnect the X6 harness connector at the K9 Body Control Module, ignition ON.
  2. Test for less than 1 V between the control circuit terminal 4 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the A23P Door Latch Assembly - Passenger, A23LR Door Latch Assembly - Left Rear, and A23RR Door Latch Assembly - Right Rear, 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, connect the X6 harness connector at the K9 Body Control Module. Disconnect the harness connector at the appropriate passenger or rear A23 Door Latch Assembly.
    4. NOTE:

    Leaving the DMM connected between a control circuit and ground for greater than 20 s may cause the K9 Body Control Module to interpret the test as a system fault and will cause the voltage on the control circuit to drop to 0 V. If the voltage drops to 0 V, operate the door locks using the door lock switch to restore the voltage for testing.

  4. Test for greater than 3 V between the control circuit terminal listed below and ground:
    • A23P Door Latch Assembly-Passenger - control circuit terminal 8
    • A23P Door Latch Assembly-Passenger - control circuit terminal 9
    • A23RR Door Latch Assembly-Right Rear - control circuit terminal 8
    • A23RR Door Latch Assembly-Right Rear - control circuit terminal 9
    • A23LR Door Latch Assembly-Left Rear - control circuit terminal 7
    • A23LR Door Latch Assembly-Left Rear - control circuit terminal 8
    • If 3 V or less 
    1. Ignition OFF, disconnect the X6 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 on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance on the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If greater than 3 V 
    5. NOTE:

    When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 00.00 V.

  5. Install a DMM between the control circuits listed below. Set the DMM to capture DC voltage using the MIN MAX function. Turn off autorange and manually set the DMM range to 00.00 V.
    • A23P Door Latch Assembly-Passenger - control circuit terminal 8 and control circuit terminal 9
    • A23RR Door Latch Assembly-Right Rear - control circuit terminal 8 and control circuit terminal 9
    • A23LR Door Latch Assembly-Left Rear - control circuit terminal 7 and control circuit terminal 8
  6. Lock and unlock the vehicle doors using the S13D Door Lock Switch-Driver.
  7. Verify the MAX voltage captured by the DMM is greater than 10 V.
    • If 10 V or less 

      Replace the K9 Body Control Module.

    • If greater than 10 V 
  8. Test or replace the A23 Door Latch Assembly.

All Door Locks Inoperative

  1. Ignition OFF and all vehicle systems OFF, disconnect the X6 harness connector at the K9 Body Control Module. 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 3 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 circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Disconnect the X2 harness connector at the K9 Body Control Module, ignition ON.
  4. Verify a test lamp illuminates between the B+ circuit terminal 4 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
      • If the test lamp does not illuminate and the circuit fuse is open 
    3. Ignition OFF.
    4. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    5. Disconnect the harness connector at each of the A23 Door Latch Assemblies.
    6. Test for infinite resistance between each control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the appropriate A23 Door Latch Assembly.
    • If the test lamp illuminates 
  5. Ignition OFF, connect the X2 harness connector at the K9 Body Control Module. Disconnect the X2 harness connector at the X50A Fuse Block - Underhood, ignition ON.
  6. Test for less than 1 V between the control circuit terminals listed below and ground:
    • K9 Body Control Module control circuit terminal 1 X6
    • K9 Body Control Module control circuit terminal 4 X6
    • X50A Fuse Block - Underhood control circuit terminal 4 X2
    • X50A Fuse Block - Underhood control circuit terminal 5 X2
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the A23D Door Latch Assembly - Driver, A23P Door Latch Assembly - Passenger, A23LR Door Latch Assembly - Left Rear, and A23RR Door Latch Assembly - Right Rear, 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 
  7. Test for infinite resistance between the control circuit terminals listed below and ground:
    • K9 Body Control Module control circuit terminal 1 X6
    • K9 Body Control Module control circuit terminal 4 X6
    • X50A Fuse Block - Underhood control circuit terminal 4 X2
    • X50A Fuse Block - Underhood control circuit terminal 5 X2
    • If less than infinite resistance 
    1. Ignition OFF, disconnect the harness connector at the A23D Door Latch Assembly - Driver, A23P Door Latch Assembly - Passenger, A23LR Door Latch Assembly - Left Rear, and A23RR Door Latch Assembly - Right Rear.
    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 
  8. Ignition OFF, connect the X2 harness connector at the X50A Fuse Block - Underhood, ignition ON.
  9. Test for less than 1 V between the K9 Body Control Module control circuit terminal 2 X6 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the X2 harness connector at the X50A Fuse Block - Underhood, 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 the circuit tests normal, test or replace the X50A Fuse Block - Underhood.
    • If less than 1 V 
  10. Test for infinite resistance between the control circuit terminal 2 X6 and ground.
    • If less than infinite resistance 
    1. Ignition OFF, disconnect the X2 harness connector at the X50A Fuse Block - Underhood.
    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 the circuit tests normal, test or replace the X50A Fuse Block - Underhood.
    • If infinite resistance 
  11. Test or replace the K9 Body Control Module.
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