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Circuit/System Testing

NOTE:
  • Terminal and connector identifiers will be different depending on the individual device being tested. Use Schematic Reference and Connector End View Reference to identify device's connector, B+, 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 the ground circuit terminal 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. Ignition ON.
  4. Verify a test lamp illuminates between the 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 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 terminal and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the S56 Radio Control Multifunction Switch.
    • If the test lamp illuminates 
  5. Ignition ON.
  6. Test for 2-12 V between the serial data circuit terminal and ground.
    • If less than 2 V 
    1. Ignition OFF, disconnect the harness connector at the A22 Radio Controls.
    2. Test for infinite resistance between the serial data circuit terminal 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 serial data circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Replace the A22 Radio Controls.
    • If greater than 12 V 
    1. Ignition OFF, disconnect the harness connector at the A22 Radio Controls.
    2. Ignition ON.
    3. Test for less than 1 V between the serial data circuit terminal and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    4. Replace the A22 Radio Controls.
    • If between 2-12 V 
  7. Replace the S56 Radio Control Multifunction Switch.
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