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Circuit/System Testing

WARNING: This page is about a different car, the 2018 Buick Envision. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF and all vehicle systems OFF, disconnect the X1 harness connector at the X50A Fuse Block - Underhood. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the X50A Fuse Block - Underhood ground circuit terminal 53 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. Connect the X1 harness connector at the X50A Fuse Block - Underhood and disconnect the X4 harness connector at the K9 Body Control Module, ignition ON.
  4. Verify the G24 Windshield Washer Pump is not activated.
    • If the G24 Windshield Washer Pump is activated 
    1. Ignition OFF, disconnect the X2 harness connector at the X50A Fuse Block - Underhood, ignition ON.
    2. Test for less than 1 V between the X50A Fuse Block - Underhood control circuit terminal 25 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, test or replace the X50A Fuse Block - Underhood.
    • Go to next step: If the G24 Windshield Washer Pump is not activated 
  5. Connect a 10 A fused jumper wire between the control circuit terminal 14 X4 and B+.
  6. Verify the G24 Windshield Washer Pump activates.
    • If the G24 Windshield Washer Pump does not activate 
    1. Ignition OFF, remove the jumper wire, disconnect the X2 harness connector at the X50A Fuse Block - Underhood.
    2. Test for infinite resistance between the X50A Fuse Block - Underhood control circuit terminal 25 X2 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 X50A Fuse Block - Underhood.
    • Go to next step: If the G24 Windshield Washer Pump activates 
  7. Replace the K9 Body Control Module.
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