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Home >> Cadillac >> 2017 >> CT6 Plug-In >> Repair and Diagnosis >> Accessories & Equipment >> Anti-Theft Systems >> Keyless Entry System And Remote Functions >> Diagnostic Information and Procedures >> Garage Door Opener Malfunction >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the S25 Garage Door Opener.
  2. Test for less than 10 Ω between the ground circuit terminal 3 and ground.
    • If 10 Ω or greater 

      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.
  4. Verify a test lamp illuminates between the B+ circuit terminal 1 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, 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 S25 Garage Door Opener.
    • If the test lamp illuminates 
  5. Verify the LED on the S25 Garage Door Opener illuminates or flashes when each button on the S25 Garage Door Opener is pressed.
    • If the LED does not illuminate or flash when each button is pressed 

      Replace the S25 Garage Door Opener.

    • If the LED illuminates or flashes when each button is pressed 
  6. Press and hold the two outer buttons on the S25 Garage Door Opener for greater than 30 s. The LED on the S25 Garage Door Opener will illuminate for 20 s, then begin to flash quickly for another 10 s. When the LED stops flashing, the system has been cleared and placed into default mode.
    NOTE: This step will clear any learned transmitters from the S25 Garage Door Opener. This will require reprogramming by the customer to reestablish universal home remote functionality.
  7. Place the J 41540  Universal Home Remote Tester so that it is adjacent to the S25 Garage Door Opener.
  8. Verify the appropriate J 41540  Universal Home Remote Tester Indicator Lights illuminate when each button on S25 Garage Door Opener the is pressed, one at a time
    • If the tester does not respond to each button press 

      Replace the S25 Garage Door Opener.

    • If the tester responds to each button press 
  9. Using the Hand Held Transmitter from the J 41540  Universal Home Remote Tester kit, program a single button on the S25 Garage Door Opener. Refer to the instructions provided with the J 41540  Universal Home Remote Tester for programming instructions.
  10. Verify the Programmed indicator on the J 41540  Universal Home Remote Tester illuminates when the programmed button on the S25 Garage Door Opener is pressed.
    NOTE: When performing step 10, press the button that was programmed in step 9.
    • If the Programmed indicator does not illuminate when the programmed button is pressed 

      Replace the S25 Garage Door Opener.

    • If the Programmed indicator illuminates when the programmed button is pressed 
  11. Instruct the customer to program the S25 Garage Door Opener to their device. Refer to the vehicle owners manual. If further malfunction occurs, a possible rolling code or incompatibility with the S25 Garage Door Opener will prevent programming.