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Circuit/System Testing

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.

Green LED Test

  1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at the A10 Inside Rearview Mirror. It may take up to 2 min for all vehicle systems to power down. Doors closed, courtesy lamps OFF.
  2. Test for less than 10 Ω between the ground circuit terminal 5 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.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON.
  4. Test for less than 1 V between the control circuit terminal 6 and ground while commanding the Green Indicator OFF with a scan tool.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the X1 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit terminal 6 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K73 Telematics Communication Interface Control Module.
    • Go to next step: If less than 1 V 
  5. Test for greater than 8 V between the control circuit terminal 6 and ground while commanding the Green Indicator ON with a scan tool.
    • If 8 V or less 
    1. Ignition OFF, disconnect the X1 harness connector at the K73 Telematics Communication Interface Control Module.
    2. Test for infinite resistance between the control circuit terminal 6 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: 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 K73 Telematics Communication Interface Control Module.
    • Go to next step: If greater than 8 V 
  6. Test or replace the A10 Inside Rearview Mirror.

Red LED Test

  1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at the A10 Inside Rearview Mirror. It may take up to 2 min for all vehicle systems to power down. Doors closed, courtesy lamps OFF.
  2. Test for less than 10 Ω between the ground circuit terminal 5 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.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON.
  4. Test for less than 1 V between the control circuit terminal 7 and ground while commanding the Red Indicator OFF with a scan tool.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the X1 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit terminal 7 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K73 Telematics Communication Interface Control Module.
    • Go to next step: If less than 1 V 
  5. Test for greater than 8 V between the control circuit terminal 7 and ground while commanding the Red Indicator ON with a scan tool.
    • If 8 V or less 
    1. Ignition OFF, disconnect the X1 harness connector at the K73 Telematics Communication Interface Control Module.
    2. Test for infinite resistance between the control circuit terminal 7 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: 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 K73 Telematics Communication Interface Control Module.
    • Go to next step: If greater than 8 V 
  6. Test or replace the A10 Inside Rearview Mirror.
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