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Circuit/System Testing

    NOTE:
    • Use the schematic to identify the following:
      • Control module and LIN device locations on the serial data circuit.
      • The control module serial data circuit terminals and the LIN device B+, ignition, ground, and serial data circuit terminals.
    • A loss of serial data communications DTC does not represent a failure of the master control module that set it.
  1. Ignition OFF, disconnect the harness connector at the S56 radio control multifunction switch.
  2. Test for less than 10 Ω between ground circuit and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between B+ circuit and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the S56 radio control multifunction switch.
  4. Test for 2-12 V between the serial data circuit and ground.
    • If greater than the specified range, test the serial data circuit for a short to voltage. If the circuit tests normal, replace the A22 radio controls.
    • If less than the specified range, test the serial data circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the A22 radio controls.
  5. If all circuits test normal, replace the S56 radio control multifunction switch.
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