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Home >> Cadillac >> 2016 >> XTS Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Engine Controls And Fuel - 3.6L (LFX LF3) - DTC P05CC To P2635 And Diagnostic Information And Procedures >> Diagnostic Information and Procedures >> DTC P0641, P0651, P0697, or P06A3: 5V Reference 1 Circuit/5V Reference 2 Circuit/5V Reference 3 Circuit/5V Reference 4 Circuit (ECM) >> Circuit/System Testing
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Circuit/System Testing

NOTE:

Additional DTCs will set when disconnecting the components.

  1. Ignition OFF, disconnect the harness connector at all appropriate sensors for the applicable DTC. Refer to Diagnostic Aids.
  2. Ignition ON.
  3. Test for 4.8-5.2 V between one of the 5V reference circuits and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the harness connectors at the K20 Engine Control Module.
    2. Test for infinite resistance between the 5V reference circuit for each applicable component and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K20 Engine Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF, disconnect the harness connectors at the K20 Engine Control Module.
    2. Test for less than 1 V between the 5V reference circuit for each applicable component and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K20 Engine Control Module.
    • If between 4.8-5.2 V 
    4. NOTE:

    A short to voltage or ground on the signal circuit of certain components may cause this DTC to set.

  4. Verify the appropriate scan tool 5V Reference 1, 2, 3, or 4 Circuit Status parameter displays OK while connecting each component associated with the 5V reference circuit one at a time.
    • If OK is not displayed when a component is connected 

      Test the signal circuit of that component for a short to ground or voltage. If the circuit tests normal, replace the component.

    • If OK is displayed after all components have been connected 
  5. All OK.
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