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July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Circuit/System Testing

Power Supply Transformer Circuit Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the T19 Power Supply Transformer. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between each ground circuit terminal 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.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON.
  4. Verify a test lamp illuminates between each B+ circuit terminal and ground.
    • If the test amp 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 
    1. Ignition OFF.
    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, test or replace the T19 Power Supply Transformer.
      • Go to next step: If the test lamp illuminates 
  5. Verify a test lamp illuminates between each ignition circuit 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 ignition circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than If 2 Ω, verify. Refer to Power Mode Mismatch .
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    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, test or replace the T19 Power Supply Transformer.
    • Go to next step: If the test lamp illuminates 
  6. Install a test lamp between the control circuit terminal 5 and ground.
  7. Verify the test lamp illuminates while cranking the engine.
    • If the test lamp does not illuminate 
    1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K20 Engine Control Module and disconnect the KR27 Starter Relay.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: 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 K20 Engine Control Module.
    • Go to next step: If the test lamp illuminates 
  8. Test or replace the T19 Power Supply Transformer.


Stop/Start Switch Malfunction

  1. Ignition OFF, disconnect the X6 electrical connector at the K9 Body Control Module, ignition ON.
  2. Verify the auto stop/start disable indicator on the auto stop/start disable switch is not illuminated.
    • If the auto stop/start disable indicator is illuminated 

      Repair the short to voltage on circuit 1110

    • Go to next step: If the auto stop/start disable indicator is not illuminated 
  3. Disconnect the X1 electrical connector at the K9 Body Control Module.
  4. Test for infinite resistance between signal circuit terminal 15 and ground.
    • If less than infinite resistance 
    1. Test circuit 1111 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    2. Replace the S48C Multifunction Switch 1 - Instrument Panel Switch.
    • Go to next step: If infinite resistance 
  5. Test for less than infinite resistance between signal circuit terminal 15 and ground while pressing and holding the auto stop/start disable switch.
    • If infinite resistance 
    1. Test circuit 1651 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit or ground connection.
      • Go to next step: If an open/high resistance is not found
    2. Test circuit 1111 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found
    3. Ignition On Vehicle in Service Mode.
    4. Test Circuit 1111 for a short to voltage.
      • If Short to voltage is found repair the fault on the circuit.
      • Go to next step: If Short to voltage is not found
    5. Replace the S48C Multifunction Switch 1 - Instrument Panel Switch.
    • Go to next step: If less than infinite resistance 
  6. Connect a 3 A jumper wire between control circuit terminal 20 X 6 and B+.
  7. Verify the auto stop/start disable indicator on the auto stop/start disable switch is illuminated.
    • If the auto stop/start disable indicator is not illuminated 
    1. Test circuit 1110 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    2. Test circuit 1110 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found
    3. Replace the S48C Multifunction Switch 1 - Instrument Panel Switch.
    • Go to next step: If the auto stop/start disable indicator is illuminated 
  8. Replace the K9 Body Control Module.

Stop/Start System Malfunction

    NOTE:
    • Circuit/System Verification must be performed before proceeding with Circuit/System Testing.
    • If the DTC set only as a history DTC, do not replace any components.
  1. Ignition Off, disconnect the connector at the T19 Multifunction Power Supply Converter.
  2. Verify a test lamp illuminates between ground circuit terminal 7 and B+.
    • If the test lamp does not illuminate 

      Repair the open/high resistance on circuit 2550 or the ground connection.

    • Go to next step: If the test lamp illuminates 
  3. Verify a test lamp illuminates between ground circuit terminal 12 and B+.
    • If the test lamp does not illuminate 

      Repair the open/high resistance on circuit 2550 or the ground connection.

    • Go to next step: If the test lamp illuminates 
  4. Verify a test lamp illuminates between B+ circuit terminal 11 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Test circuit 6240 for an open/high resistance.
      • if an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open or high resistance is not found
    2. 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. Test circuit 6240 for a short to ground
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    2. Test circuit 2172 for a short to ground
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    3. Replace the T19 Multifunction Power Supply Converter.
    • Go to next step: If the test lamp illuminates 
  5. Using the schematics, identify and remove any fuses powered by control circuit 2172.
  6. Test for less than 1 V between control circuit terminal 10 and ground.
    • If 1 or greater 

      Repair the short to voltage on circuit 2172.

    • Go to next step: If less than 1 V 
  7. Ignition OFF.
  8. Test for infinite resistance between control circuit terminal 10 and ground.
    • If less than infinite resistance 

      Repair the short to ground on circuit 2172.

    • Go to next step: If infinite resistance 
  9. Verify a test lamp illuminates between B+ circuit terminal 8 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Test circuit 6340 for an open/high resistance.
      • if an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open or high resistance is not found
    2. 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. Test circuit 6340 for a short to ground
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    2. Test circuit 2173 for a short to ground
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    3. Replace the T19 Multifunction Power Supply Converter.
    • Go to next step: If the test lamp illuminates 
  10. Using the schematics, identify and remove any fuses powered by control circuit 2173.
  11. Test for less than 1 V between control circuit terminal 9 and ground.
    • If 1 or greater 

      Repair the short to voltage on circuit 2173.

    • Go to next step: If less than 1 V 
  12. Ignition OFF.
  13. Test for infinite resistance between control circuit terminal 9 and ground.
    • If less than infinite resistance 

      Repair the short to ground on circuit 2173.

  14. Ignition ON.
  15. Verify a test lamp illuminates between terminal 4 and ground.
    • If the test lamp does not illuminate 
    1. Test circuit 4320 for an open/high resistance.
      • if an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open or high resistance is not found
    2. Test circuit 4320 for a short to ground
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    3. Replace the K20 Engine Control Module.
    • Go to next step: If the test lamp turns illuminates 
  16. Ignition Crank.
  17. Verify a test lamp illuminates between terminal 5 and ground while the engine is cranking.
    • If the test lamp does not illuminate 
    1. Test circuit 625 for an open/high resistance.
      • if an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open or high resistance is not found
    2. Test circuit 625 for a short to ground
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    3. Replace the K20 Engine Control Module.
    • Go to next step: If the test lamp illuminates 
  18. Replace the T19 Multifunction Power Supply Converter.
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