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Circuit/System Testing

WARNING: This page is about a different car, the 2017 Chevrolet Spark. 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 harness connector at the appropriate A9 Outside Rearview Mirror. It may take up to 2 min for all vehicle systems to power down.
  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.
    • If less than 10 Ω 
  3. Connect a test lamp between the control circuit terminal 8 and ground, ignition ON.
  4. Verify the test lamp does not turn ON and OFF when commanding the Rear Defogger On and Off with a scan tool.
    • If the test lamp turns ON and OFF 

      Test or replace the E17 Outside Rearview Mirror Glass.

    • If the test lamp does not turn ON and OFF 
  5. Ignition OFF, connect the harness connector at the A9 Outside Rearview Mirror. Disconnect the X1 harness connector at the X50A Fuse Block-Underhood, ignition ON.
  6. Verify the A9 Outside Rearview Mirror is not warm.
    • If the A9 Outside Rearview Mirror is warm 
    1. Ignition OFF, disconnect the harness connector at the A9 Outside Rearview Mirror, ignition ON.
    2. Test for less than 1 V between the A9 Outside Rearview Mirror control circuit terminal 8 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, test or replace the E17 Outside Rearview Mirror Glass.
    • If the A9 Outside Rearview Mirror is not warm 
  7. Connect a 15 A fused jumper wire between the control circuit terminal 61 X1 and B+:
  8. Verify the A9 Outside Rearview Mirror warms.
    • If the A9 Outside Rearview Mirror does not warm 
    1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the A9 Outside Rearview Mirror.
    2. Test for infinite resistance between the A9 Outside Rearview Mirror control circuit terminal 8 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, test or replace the E17 Outside Rearview Mirror Glass.
    • If the A9 Outside Rearview Mirror warms 
  9. Replace the X50A Fuse Block-Underhood.
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