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Circuit/System Testing

NOTE:

Use the schematics and connector end views to identify the device's ground, B+, and serial data circuit terminals.

  1. Ignition OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3m (9.8ft) away from vehicle. Disconnect all the harness connectors at the A10 Inside Rearview Mirror. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10Ω between each ground circuit terminal and ground.
    • If 10Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2Ω in the ground circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, repair the open/high resistance in the ground connection.
    • If less than 10Ω 
  3. Ignition ON.
  4. Verify a test lamp illuminates between each B+ circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2Ω in the B+ circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, verify the fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the A10 Inside Rearview Mirror.
    • If the test lamp illuminates 
  5. Ignition OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3m (9.8ft) away from vehicle. Disconnect the harness connectors at the device setting the DTC. It may take up to 2 minutes for all vehicle systems to power down.
  6. Test for less than 2Ω in each of the serial data circuits end to end between the A10 Inside Rearview Mirror and the device setting the DTC.
    • If 2Ω or greater 

      Repair the open/high resistance in the serial data circuit between the A10 Inside Rearview Mirror and the device setting the DTC or a serial data splice pack.

    • If less than 2Ω 
  7. Replace the A10 Inside Rearview Mirror.
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