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Home >> Chevrolet >> 2017 >> Sonic Premier, 4D Hatchback, Standard Trans >> Repair and Diagnosis >> Body & Frame >> Ignition Switch/Steering Lock >> Diagnostic Information And Procedures >> Diagnostic Information and Procedures >> Ignition Mode Switch Indicator Malfunction >> Circuit/System Testing

Circuit/System Testing

Green LED Test

  1. Ignition OFF, disconnect the X2 harness connector at the K9 Body Control Module, Ignition ON.
  2. Verify a test lamp illuminates between the B+ circuit terminal 1 and ground.
    • 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 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 
    1. Ignition OFF, 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 the circuit.
      • If infinite resistance, replace the K9 Body Control Module
    • If the test lamp illuminates 
  3. Ignition OFF, Connect the X2 harness connector at the K9 Body Control Module.
  4. 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.
  5. 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 connections.
    • If less than 10 Ω 
  6. Connect the harness connector at the S38 Ignition Mode Switch.
  7. Ignition ON, disconnect the harness connector at the S38 Ignition Mode Switch.
  8. Connect a test lamp between the control circuit terminal 5 and ground.
  9. Verify the test lamp stays OFF when commanding Run/Start Power Mode Indicator Off with the scan tool.
    • If the test lamp is always ON 
    1. Connect the harness connector at the S38 Ignition Mode Switch.
    2. Ignition OFF, remove the test lamp, disconnect the harness connector at the K9 Body Control Module.
    3. Ignition ON, disconnect the harness connector at the S38 Ignition Mode Switch.
    4. 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, replace the K9 Body Control Module.
    • If the test lamp is always OFF 
  10. Test for greater than 3 V between the control circuit terminal 5 and ground while commanding Run/Start Power Mode Indicator On with the scan tool.
    • If 3 V or less 
    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 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 in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If 3 V or greater 
  11. Test or replace the S38 Ignition Mode Switch.

Amber LED Test

  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 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 connections.
    • If less than 10 Ω 
  3. Connect the harness connector at the S38 Ignition Mode Switch.
  4. Ignition ON, disconnect the harness connector at the S38 Ignition Mode Switch.
  5. Connect a test lamp between the control circuit terminal 2 and ground.
  6. Verify the test lamp stays OFF when commanding Accessory Power Mode Indicator Off with the scan tool.
    • If the test lamp is always ON 
    1. Connect the harness connector at the S38 Ignition Mode Switch.
    2. Ignition OFF, remove the test lamp, disconnect the harness connector at the K9 Body Control Module.
    3. Ignition ON, disconnect the harness connector at the S38 Ignition Mode Switch.
    4. 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, replace the K9 Body Control Module.
    • If the test lamp is always OFF 
  7. Test for greater than 3 V between the control circuit terminal 2 and ground while commanding Accessory Power Mode Indicator On with the scan tool.
    • If 3 V or less 
    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 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 in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If 3 V or greater 
  8. Test or replace the S38 Ignition Mode Switch.
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