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Circuit/System Testing

NOTE: Additional DTCs may set when disconnecting components.
  1. Ignition OFF, disconnect the harness connector of all the sensors connected to the 5 V reference bus for the applicable DTC. Refer to Circuit/System Description.
    2. NOTE: A short to voltage on the signal circuit of certain components may cause this DTC to set.
  2. Ignition ON, test for 4.8-5.2 V between one of the 5 V reference circuits and ground.
    • If less than the specified range, test all of the 5 V reference circuits for a short to ground. If all circuits test normal, replace the K20 ECM.
    • If greater than the specified range, test for a short to voltage on all of the 5 V reference circuits or the signal circuit for each component associated with the appropriate 5 V reference bus for a short to voltage. If all circuits test normal, replace the K20 ECM.
  3. Connect each component associated with the 5 V reference bus, one at a time, while monitoring the voltage. Verify the voltage remains between 4.8-5.2 V.
    • If not within the specified range when a component is connected, test the signal circuit for a short to voltage. If the circuit tests normal, replace the component.
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