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Circuit/System Testing

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DTC B3948

  1. Ignition OFF, exterior lamps OFF, remove the appropriate E4 Turn Signal Lamp bulb listed below.
    • E4LF Turn Signal Lamp - Left Front
    • E4Y Turn Signal Repeater Lamp - Left
  2. Test for less than 5 Ω between the appropriate ground circuit terminal listed below and ground.
    • E4LF Turn Signal Lamp - Left Front socket terminal
    • E4Y Turn Signal Repeater Lamp - Left terminal 1
    • If 5 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.
    • Go to next step: If less than 5 Ω 
  3. Connect a test lamp between the appropriate control circuit terminal listed below and ground, ignition ON.
    • E4LF Turn Signal Lamp - Left Front socket terminal
    • E4Y Turn Signal Repeater Lamp - Left terminal 2
  4. Verify the test lamp turns ON and OFF when commanding the Left Front Turn Signal Lamp ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the X5 harness connector at the K9 Body 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.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the X5 harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit terminal and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K9 Body Control Module.
    • Go to next step: If the test lamp turns ON and OFF 
  5. Test or replace the appropriate E4 Turn Signal Lamp - Left.

DTC B3949

  1. Ignition OFF, exterior lamps OFF, remove the appropriate E4 Turn Signal Lamp bulb listed below.
    • E4RF Turn Signal Lamp - Right Front
    • E4Z Turn Signal Repeater Lamp - Right
  2. Test for less than 5 Ω between the appropriate ground circuit terminal listed below and ground.
    • E4RF Turn Signal Lamp - Right Front socket terminal
    • E4Z Turn Signal Repeater Lamp - Right terminal 1
    • If 5 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.
    • Go to next step: If less than 5 Ω 
  3. Connect a test lamp between the appropriate control circuit terminal listed below and ground, ignition ON.
    • E4RF Turn Signal Lamp - Right Front socket terminal
    • E4Z Turn Signal Repeater Lamp - Right terminal 2
  4. Verify the test lamp turns ON and OFF when commanding the Right Front Turn Signal Lamp ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the X4 harness connector at the K9 Body 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.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the X4 harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit terminal and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K9 Body Control Module.
    • Go to next step: If the test lamp turns ON and OFF 
  5. Test or replace the appropriate E4 Turn Signal Lamp - Right.
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