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Switch Indicator LED Backlighting Malfunction

WARNING: This page is about a different car, the 2016 Chevrolet Malibu Limited. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel. It may take up to 10 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 7 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Ignition ON, place the Dimmer Switch in the HIGH position for high backlighting intensity.
  4. Verify a test lamp illuminates between the control circuit terminal 4 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.
    • If the test lamp does not illuminate 
    1. Ignition 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 
  5. Place the S36 Instrument Panel Dimmer Switch in the LOW position for low backlighting intensity.
  6. Verify a test lamp does not illuminate at FULL intensity between the control circuit terminal 3 and ground.
    • If the test lamp illuminates at full intensity 
    1. Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module, ignition ON.
    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 
  7. Test or replace the appropriate S48A Multifunction Switch - Instrument Panel.