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Circuit/System Testing

  1. Ignition OFF/Vehicle OFF, disconnect the harness connectors at the components listed below.
    • S48B Multifunction Switch - Overhead Console
    • S48C Multifunction Switch 1 - Instrument Panel
    • S48D Multifunction Switch 2 - Instrument Panel
  2. Ignition ON/vehicle in Service Mode, place the S36 Instrument Panel Dimmer Switch in the HIGH position for high backlighting intensity.
  3. Verify a test lamp illuminates between each control circuit terminal listed below and ground.
    NOTE: The test lamp in the following step will illuminate at LOW intensity. This is normal circuit operation and does not indicate a circuit malfunction.
    • S48B Multifunction Switch - Overhead Console terminal 5
    • S48C Multifunction Switch 1 - Instrument Panel terminal 2
    • S48D Multifunction Switch 2 - Instrument Panel terminal 8
    • If the test lamp does not illuminate 
    1. Ignition OFF/Vehicle OFF, disconnect the X1 harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the control 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 control 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.
    • If the test lamp illuminates 
  4. Place the S36 Instrument Panel Dimmer Switch in the LOW position for low backlighting intensity.
  5. Verify a test lamp does not illuminate at FULL intensity between each control circuit terminal listed below and ground.
    • S48B Multifunction Switch - Overhead Console terminal 5
    • S48C Multifunction Switch - Instrument Panel terminal 2
    • S48D Multifunction Switch 2 - Instrument Panel terminal 8
    • If the test lamp illuminates at full intensity 
    1. Ignition OFF/Vehicle OFF, disconnect the X1 harness connector at the K9 Body Control Module, ignition ON/vehicle in Service Mode.
    2. Test for less than 1 V between the control circuit terminal and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K9 Body Control Module.
    • If the test lamp does not illuminate at full intensity 
  6. Test or replace the appropriate S48 Multifunction Switch.
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