LEMON Manuals: Even more car manuals for everyone
Home >> Cadillac >> 2017 >> CT6 Plug-In >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Keyless Entry System And Remote Functions >> Diagnostic Information and Procedures >> Keyless Entry System Malfunction (Passive) >> Circuit/System Testing >> Antenna Circuit Malfunction

Antenna Circuit Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate T10 Keyless Entry Antenna, ignition ON.
  2. Test for less than 1 V between the signal circuit terminal 1 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the K84 Keyless Entry Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K84 Keyless Entry Control Module.
    • If less than 1 V 
  3. Ignition OFF, install a DMM between the signal circuit terminal 1 and ground. Set the DMM to capture DC voltage using the MIN MAX function. Turn off autorange and manually set the DMM range to 000.0 V.
    NOTE: When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 000.0 V.
  4. Lock the vehicle doors using the keyless entry transmitter. Activate the antenna by operating the appropriate exterior door handle/rear closure touch pad.
  5. Verify the MAX voltage captured by the DMM is greater than 1 V.
    • If 1 V or less 
    1. Ignition OFF, disconnect the harness connector at the K84 Keyless Entry Control Module.
    2. Test for infinite resistance between the signal circuit 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 signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K84 Keyless Entry Control Module.
    • If greater than 1 V 
  6. Test for less than 1 V between the low reference circuit terminal 2 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the K84 Keyless Entry Control Module, ignition ON.
    2. Test for less than 1 V between the low reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K84 Keyless Entry Control Module.
    • If less than 1 V 
  7. Install a DMM between the signal circuit terminal 1 and the low reference circuit terminal 2. Set the DMM to capture DC voltage using the MIN MAX function. Turn off autorange and manually set the DMM range to 000.0 V.
    NOTE: When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 000.0 V.
  8. Lock the vehicle doors using the keyless entry transmitter. Activate the antenna by operating the appropriate exterior door handle/rear closure touch pad.
  9. Verify the MAX voltage captured by the DMM is greater than 1 V.
    • If 1 V or less 
    1. Ignition OFF, disconnect the harness connector at the K84 Keyless Entry Control Module.
    2. Test for infinite resistance between the low reference circuit 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 low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K84 Keyless Entry Control Module.
    • If greater than 1V 
  10. Replace the appropriate T10 Keyless Entry Antenna.
  11. Lock the vehicle doors using the keyless entry transmitter. Activate the antenna by operating the appropriate exterior door handle/rear closure touch pad.
  12. Verify that the door/rear compartment unlocks and opens when the exterior door handle/rear closure touch pad is operated.
    • If the door/rear compartment does not unlock and open 

      Replace the K84 Keyless Entry Control Module.

    • If the door/rear compartment unlocks and opens 
  13. All OK.
scientia non olet · About LEMON Manuals