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Circuit / System Testing

  1. Ignition OFF and all vehicle systems OFF, scan tool disconnected, disconnect the harness connector at the K77 Remote Control Door Lock Receiver. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 30 Ω between the low reference circuit terminal 4 and ground.
    • If 30 Ω or greater 
      1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
      2. Test for less than 2 Ω in the low reference circuit end to end.
        • If 2 Ω or greater, repair the open/high resistance in the circuit.
        • If less than 2 Ω, replace the K9 Body Control Module.
    • Go to next step: If less than 30 Ω 
  3. Ignition ON.
  4. Test for 5 V between the B+ circuit terminal 1 and ground.
    • If less than 5 V 
      1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
      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.
      3. 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, replace the K9 Body Control Module.
    • Go to next step: If greater than 5 V 

      Repair the short to voltage

    • Go to next step: If 5 V 
  5. Test for 5 V between the B+ circuit terminal 3 and ground.
    • If less than 5 V 
      1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
      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.
      3. 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, replace the K9 Body Control Module.
    • Go to next step: If greater than 5 V 

      Repair the short to voltage

    • Go to next step: If 5 V 
  6. Verify the keyless entry functions operate.
    • If the keyless entry functions do not operate 

      Replace the K9 Body Control Module

    • Go to next step: If the keyless entry functions operate 
  7. All OK.
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