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Circuit/System Testing

  1. Ignition OFF and all systems OFF, disconnect the harness connector at the S38 Ignition Mode Switch. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10Ω between the ground circuit terminal 4 and ground.
    • If 10Ω or greater 
    1. Test for less than 2Ω in the ground circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, repair the open/high resistance in the ground connection.
    • If less than 10Ω 
  3. Test for less than 10Ω between the low reference circuit terminal 7 and ground.
    • If 10Ω or greater 
    1. Test for less than 2Ω in the ground circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K84 Keyless Entry Control Module.
    • If less than 10Ω 
  4. Connect the S38 Ignition Mode Switch, ignition ON.
  5. Disconnect the S38 Ignition Mode Switch.
  6. Verify the scan tool Body Control Module Push Button Ignition Switch Voltage parameter is greater than 11V.
    • If 11V or less 
    1. Connect the S38 Ignition Mode Switch.
    2. Ignition OFF, disconnect the harness connector at the K9 Body Control Module and S38 Ignition Mode Switch.
    3. Test for infinite resistance between the signal circuit terminal 6 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 greater than 11V 
  7. Install a 3A fused jumper wire between the signal circuit terminal 6 and ground.
  8. Verify the scan tool Body Control Module Push Button Ignition Switch Voltage parameter is less than 1V.
    • If 1V or greater 
    1. Disconnect the harness connector at the K9 Body Control Module.
    2. Test for less than 1V between the signal circuit and ground.
      • If 1V or greater, repair the short to voltage on the circuit.
      • If less than 1V
    3. Test for less than 2Ω in signal circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K9 Body Control Module.
    • If less than 1V 
  9. Connect the harness connector at the S38 Ignition Mode Switch.
  10. Verify the scan tool Body Control Module Push Button Ignition Switch Voltage parameter is 8-10V, with the S38 Ignition Mode Switch released.
    • If not between 8-10V 

      Test or replace the S38 Ignition Mode Switch.

    • If between 8-10V 
  11. Verify the scan tool Body Control Module Push Button Ignition Switch Voltage parameter is 4-7V, with the S38 Ignition Mode Switch pressed.
    • If not between 4-7V 

      Test or replace the S38 Ignition Mode Switch.

    • If between 4-7V 
  12. Disconnect the X1 harness connector at the K84 Keyless Entry Control Module.
  13. Test for infinite resistance between the signal circuit terminal 11 and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  14. Ignition ON.
  15. Test for less than 1V between the signal circuit terminal 11 and ground.
    • If 1V or greater 

      Repair the short to voltage on the circuit.

    • If less than 1V 
  16. Test for 4.5-5.5 kΩ between the signal circuit terminal 11 and the low reference circuit terminal 12, with the S38 Ignition Mode Switch released.
    • If not between 4.5-5.5 kΩ 
    1. Ignition OFF, disconnect the harness connector at the S38 Ignition Mode Switch.
    2. Test for less than 2Ω in signal circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, test or replace the S38 Ignition Mode Switch.
    • If between 4.5-5.5 kΩ 
  17. Test for 1-1.5 kΩ between the signal circuit terminal 11 and the low reference circuit terminal 12, with the S38 Ignition Mode Switch pressed.
    • If not between 1-1.5 kΩ 

      Test or replace the S38 Ignition Mode Switch.

    • If between 1-1.5 kΩ 
  18. Replace the K84 Keyless Entry Control Module.


Without Push Button Start

  1. Ignition OFF, disconnect the S39 Ignition Switch.
  2. Verify a test lamp illuminates between the B+ circuit terminal 2 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Remove the test lamp.
    2. Test for less than 2Ω in the B+ circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, 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 
    1. Remove the test lamp.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on one of the following circuits listed below:
        NOTE:

        To help isolate a short to ground, it may be necessary to disconnect modules that are connected to the following circuits:

      • B+ circuit terminal 2
      • Ignition circuit terminal 1
      • Ignition circuit terminal 3
      • Ignition circuit terminal 4
    • If the test lamp illuminates 
  3. Connect the S39 Ignition Switch.
  4. Ignition ON, disconnect the harness connector at the S39 Ignition Switch while the ignition is ON.
  5. Test for 4.8-5.2V between the 5V reference circuit terminal 6 and ground.
    • If less than 4.8V 
    1. Connect the S39 Ignition Switch.
    2. Ignition OFF, disconnect the X3 harness connector at the K9 Body Control Module and S39 Ignition Switch.
    3. Test for infinite resistance between the 5V reference circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    4. Test for less than 2Ω in the 5V reference circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K9 Body Control Module.
    • If greater than 5.2V 
    1. Connect the S39 Ignition Switch.
    2. Ignition OFF, disconnect the X3 harness connector at the K9 Body Control Module.
    3. Ignition ON, disconnect the harness connector at the S39 Ignition Switch while the ignition is ON.
    4. Test for less than 1V between the 5V reference circuit and ground.
      • If 1V or greater, repair the short to voltage on the circuit.
      • If less than 1V, replace the K9 Body Control Module.
    • If between 4.8-5.2V 
  6. Connect the S39 Ignition Switch.
  7. Ignition OFF.
  8. Disconnect the X3 harness connector at the K9 Body Control Module, ignition ON.
  9. Verify a test lamp illuminates between each of the ignition circuits listed below and ground:
    • Ignition circuit terminal 5
    • Ignition circuit terminal 6
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF remove the test lamp.
    2. Test for less than 2Ω in the ignition circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, 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 
    1. Ignition OFF remove the test lamp.
    2. Test for infinite resistance between the ignition circuit 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 the test lamp illuminates 
  10. Ignition OFF with the key in.
  11. Verify a test lamp illuminates between ignition circuit terminal 15 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF with the key out, remove the test lamp.
    2. Test for less than 2Ω in the ignition circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, 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 
    1. Ignition OFF with the key out remove the test lamp.
    2. Test for infinite resistance between the ignition circuit terminal 15 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 the test lamp illuminates 
  12. Connect the X3 harness connector at the K9 Body Control Module, ignition ON.
  13. Disconnect the S39 Ignition Switch.
  14. Test for less than 1V between each of the ignition circuits listed below and ground:
    • Ignition circuit terminal 1
    • Ignition circuit terminal 3
    • Ignition circuit terminal 4
    • If 1V or greater 

      Repair the short to voltage on the circuit.

    • If less than 1V 
  15. Test or replace the S39 Ignition Switch.

With Push Button Start

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S38 Ignition Mode Switch. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10Ω between the ground circuit terminal 4 and ground.
    • If 10Ω or greater 
    1. Test for less than 2Ω in the ground circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, repair the open/high resistance in the ground connection.
    • If less than 10Ω 
  3. Test for less than 10Ω between the low reference circuit terminal 7 and ground.
    • If 10Ω or greater 
    1. Test for less than 2Ω in the ground circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K84 Keyless Entry Control Module.
    • If less than 10Ω 
  4. Connect the S38 Ignition Mode Switch, ignition ON.
  5. Disconnect the S38 Ignition Mode Switch.
  6. Verify the scan tool K9 Body Control Module Push Button Ignition Switch Voltage parameter is greater than 11V.
    • If 11V or less 
    1. Connect the S38 Ignition Mode Switch.
    2. Ignition OFF, disconnect the X2 harness connector at the K9 Body Control Module and S38 Ignition Mode Switch.
    3. Test for infinite resistance between the signal circuit terminal 6 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 greater than 11V 
  7. Install a 3A fused jumper wire between the signal circuit terminal 6 and ground.
  8. Verify the scan tool K9 Body Control Module Push Button Ignition Switch Voltage parameter is less than 1V.
    • If 1V or greater 
    1. Disconnect the harness connector at the K9 Body Control Module.
    2. Test for less than 1V between the signal circuit and ground.
      • If 1V or greater, repair the short to voltage on the circuit.
      • If less than 1V
    3. Test for less than 2Ω in signal circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K9 Body Control Module.
    • If less than 1V 
  9. Connect the harness connector at the S38 Ignition Mode Switch.
  10. Verify the scan tool K9 Body Control Module Push Button Ignition Switch Voltage parameter is 8-10V, with the S38 Ignition Mode Switch released.
    • If not between 8-10V 

      Test or replace the S38 Ignition Mode Switch.

    • If between 8-10V 
  11. Verify the scan tool K9 Body Control Module Push Button Ignition Switch Voltage parameter is 4-7V, with the S38 Ignition Mode Switch pressed.
    • If not between 4-7V 

      Test or replace the S38 Ignition Mode Switch.

    • If between 4-7V 
  12. Disconnect the X1 harness connector at the K84 Keyless Entry Control Module.
  13. Test for infinite resistance between the signal circuit terminal 11 and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  14. Ignition ON.
  15. Test for less than 1V between the signal circuit terminal 11 and ground.
    • If 1V or greater 

      Repair the short to voltage on the circuit.

    • If less than 1V 
  16. Test for 4.5-5.5 kΩ between the signal circuit terminal 11 and the low reference circuit terminal 12, with the S38 Ignition Mode Switch released.
    • If not between 4.5-5.5 kΩ 
    1. Ignition OFF, disconnect the harness connector at the S38 Ignition Mode Switch.
    2. 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, test or replace the S38 Ignition Mode Switch.
    • If between 4.5-5.5 kΩ 
  17. Test for 1-1.5 kΩ between the signal circuit terminal 11 and the low reference circuit terminal 12, with the S38 Ignition Mode Switch pressed.
    • If not between 1-1.5 kΩ 

      Test or replace the S38 Ignition Mode Switch.

    • If between 1-1.5 kΩ 
  18. Replace the K84 Keyless Entry Control Module.
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