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Circuit/System Testing

  1. Ignition OFF, disconnect the X2 harness connector at the K31 Navigation Control Module, ignition ON.
  2. Test for less than 1 V between the signal circuit terminal 4 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the X1 harness connector at the A11 Radio, ignition ON.
    2. Test for less than 1 V in the signal circuit end to end.
      • If 1 V or Greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the A11 Radio.
    • Go to next step: If less than 1 V 
  3. Ignition OFF, disconnect X1 harness connector at the A11 Radio.
  4. Test for infinite resistance between the signal circuit Terminal 17 and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  5. Test for less than 2 Ω in the signal circuit end to end.
    • If 2 Ω or greater  .

      Repair the open/high resistance in the circuit

    • Go to next step: If less than 2 Ω 
  6. Replace the K31 Navigation Control Module, connect all harness connectors.
  7. Ignition ON, Radio ON.
  8. Verify DTC B12A1 is not set.
    • If DTC B12A1 is set 

      Replace A11 Radio

    • Go to next step: If DTC B12A1 is not set 
  9. All OK.
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