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Circuit/System Testing

  1. Verify a test lamp illuminates between the G13 Generator B+ circuit terminal A X2 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Remove the test lamp and disconnect the B+ cable at the G13 Generator.
    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. Remove the test lamp, disconnect the battery negative cable, and disconnect the G13 Generator B+ cable.
    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 the test lamp illuminates 
  2. Disconnect the X1 harness connector at the G13 Generator, ignition ON.
  3. Test for 3.0- 5.5 V between the control circuit terminal 1 and ground.
    • If less than 3.0 V 
    1. Ignition OFF, disconnect the harness connectors at the K20 Engine Control Module.
    2. Test for infinite resistance between the control 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 control circuit end to end.
      • If greater the 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K20 Engine Control Module.
    • If greater than 5.5 V 
    1. Ignition OFF, disconnect the harness connectors at the K20 Engine Control Module, Ignition ON.
    2. Test for less than 1 V between the control circuit and ground.
      • If greater than 1 V, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K20 Engine Control Module.
    • If between 3.0-5.5 V 
  4. Test or replace the G13 Generator.