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Home >> Cadillac >> 2017 >> CTS Base, AWD >> Repair and Diagnosis (Single Page) >> Electrical >> Motors, Switches, Relays >> Battery, Charging System And Starting System >> Diagnostic Information and Procedures >> DTC P1077, P1078, P107A, P107B, P107D, or P107E: Stop-Start Capacitor Control Module, Stop-Start Control Module >> Circuit/System Testing
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Circuit/System Testing

WARNING:

Ultracapacitors should not be opened, disassembled, crushed, burned, charged over 5V, or exposed to high temperatures greater than 81.6°C (179°F). Ultracapacitors contain acetonitrile. If ultracapacitor leaks or ruptures it will emit flammable liquid and vapor with an aromatic ether-like odor. Harmful if inhaled or absorbed through the skin. Causes respiratory tract, eye, and skin irritation. May be harmful if swallowed. Can cause target organ damage. Arcing may also occur when charged and shorted, resulting in molten metal splattering and arc-flash hazards. To reduce the risk of personal injury and/or vehicle damage:

  • Do not breath vapor or mist, assure adequate ventilation of area.
  • Do not ingest.
  • Do not eat, drink or smoke when using this product.
  • Avoid contact with eyes, skin and clothing. In case of exposure to ultracapacitor contents, wash affected area for at least 15 minutes with generous amounts of water and seek medical attention.
  • Keep away from heat sparks and flame.
  • Remove jewelry before handling.
  • Follow diagnostic and repair procedures to discharge the ultracapacitor and disconnect the negative battery terminal when requested.
NOTE:

You must perform Circuit/System Verification before Circuit/System Testing.

DTC P1077 or P1078

  1. Clear the DTCs, discharge the C10 Stop/Start Capacitor by commanding Discharge Stop/Start Capacitor with a scan tool. Wait at least 3 min to allow the capacitor to discharge.
  2. Ignition OFF, disconnect the C1 Battery (disconnect negative cable of the battery).
  3. Disconnect the X5 harness connector at the K176 Stop/Start Capacitor Control Module.
  4. Test for less than 10 Ω between the ground circuit terminal A 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 
  5. Reconnect the X5 harness connector at the K176 Stop/Start Capacitor Control Module.
    6. NOTE:

    If capacitor voltage is still present on terminal A X3 at the K176 Stop/Start Capacitor Control Module, ensure to not contact a ground point when disconnecting it.

  6. Disconnect the X3 harness connector at the K176 Stop/Start Capacitor Control Module and the X2 harness connector at the C10 Stop/Start Capacitor.
  7. Test for less than 2 Ω in the control circuit end to end.
    • If 2 Ω or greater 

      Replace the auxiliary generator battery jumper cable.

    • If less than 2 Ω 
  8. Reconnect the X3 harness connector at the K176 Stop/Start Capacitor Control Module and the X2 harness connector at the C10 Stop/Start Capacitor.
  9. Reconnect the C1 Battery.
  10. Ignition OFF, disconnect the X1 harness connector at the K176 Stop/Start Capacitor Control Module.
  11. Test for greater than 9.12 V between the B+ circuit terminal 6 and ground.
    • If less than 9.12 V 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 less than 9.12 V 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 K176 Stop/Start Capacitor Control Module.
    • If greater than 9.12 V 
  12. Replace the K176 Stop/Start Capacitor Control Module.

DTC P107A or P107B

  1. Clear the DTCs, discharge the C10 Stop/Start Capacitor by commanding Discharge Stop/Start Capacitor with a scan tool. Wait at least 3 min to allow the capacitor to discharge.
  2. Ignition OFF, disconnect the C1 Battery (disconnect negative cable of the battery).
  3. Disconnect the X5 harness connector at the K176 Stop/Start Capacitor Control Module.
  4. Test for less than 10 Ω between the ground circuit terminal A 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 
  5. Reconnect the X5 harness connector at the K176 Stop/Start Capacitor Control Module.
    6. NOTE:

    If capacitor voltage is still present on terminal A X3 at the K176 Stop/Start Capacitor Control Module, ensure to not contact a ground point when disconnecting it.

  6. Ignition OFF, disconnect the X3 harness connector at the K176 Stop/Start Capacitor Control Module and the X2 harness connector at the C10 Stop/Start Capacitor.
  7. Test for less than 2 Ω in the control circuit end to end.
    • If 2 Ω or greater 

      Replace the auxiliary generator battery jumper cable.

    • If less than 2 Ω 
  8. Reconnect the X3 harness connector at the K176 Stop/Start Capacitor Control Module and the X2 harness connector at the C10 Stop/Start Capacitor.
  9. Reconnect the C1 Battery.
  10. Ignition OFF, disconnect the X2 harness connector at the K176 Stop/Start Capacitor Control Module.
  11. Test for greater than 6.34 V between the B+ circuit terminal 1 and ground.
    • If less than 6.34 V 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 less than 6.34 V 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, replace the K176 Stop/Start Capacitor Control Module.
    • If greater than 6.34 V 
  12. Replace the K176 Stop/Start Capacitor Control Module.

DTC P107D or P107E

  1. Clear the DTCs, discharge the C10 Stop/Start Capacitor by commanding Discharge Stop/Start Capacitor with a scan tool. Wait at least 3 min to allow the capacitor to discharge.
  2. Ignition OFF, disconnect the C1 Battery (disconnect negative cable of the battery).
  3. Disconnect the X5 harness connector at the K176 Stop/Start Capacitor Control Module.
  4. Test for less than 10 Ω between the ground circuit terminal A 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 
  5. Reconnect the X5 harness connector at the K176 Stop/Start Capacitor Control Module.
    6. NOTE:

    If capacitor voltage is still present on terminal A X3 at the K176 Stop/Start Capacitor Control Module, ensure to not contact a ground point when disconnecting it.

  6. Ignition OFF, disconnect the X3 harness connector at the K176 Stop/Start Capacitor Control Module and the X2 harness connector at the C10 Stop/Start Capacitor.
  7. Test for less than 2 Ω in the control circuit end to end.
    • If 2 Ω or greater 

      Replace the auxiliary generator battery jumper cable.

    • If less than 2 Ω 
  8. Reconnect the X3 harness connector at the K176 Stop/Start Capacitor Control Module and the X2 harness connector at the C10 Stop/Start Capacitor.
  9. Reconnect the C1 Battery.
  10. Ignition OFF, disconnect the X1 harness connector at the K176 Stop/Start Capacitor Control Module.
  11. Test for greater than 62% of the measured battery voltage between the B+ circuit terminal 7 and ground.
    • If less than 62% of the measured battery voltage 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 less than 62% of the measured battery voltage 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, replace the K176 Stop/Start Capacitor Control Module.
    • If greater than 62% of the measured battery voltage 
  12. Replace the K176 Stop/Start Capacitor Control Module.
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