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Circuit/System Testing

NOTE:

Use the wiring schematics and connector end views to identify the following:

  • The master control module and the LIN devices on the same LIN serial data circuit
  • The master control module's LIN serial data circuit terminal and the LIN device's B+, ignition, ground, and LIN serial data circuit terminals
NOTE:

This diagnostic procedure is only used for B110 Battery Sensor Module connected to LIN serial data circuit coming from K20 Engine Control Module.

  1. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. Disconnect the harness connector at the B110 Battery Sensor Module. It may take up to 10 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between each ground circuit terminal and ground.
    • If 10 Ω or greater 
    1. Ignition/Vehicle 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 10 Ω 
  3. Ignition ON/Vehicle In Service Mode.
  4. If equipped, verify a test lamp illuminates between each B+ circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition/Vehicle OFF, remove the test lamp.
    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/Vehicle OFF, remove the test lamp.
    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 infinite resistance, replace the B110 Battery Sensor Module.
    • Go to next step: If the test lamp illuminates 
  5. If equipped, verify a test lamp illuminates between each ignition circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition/Vehicle OFF, remove the test lamp.
    2. Test for less than 2 Ω in the ignition 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 OK and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition/Vehicle OFF, remove the test lamp.
    2. Test for infinite resistance between the ignition circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the B110 Battery Sensor Module.
    • Go to next step: If the test lamp illuminates 
  6. If equipped, verify a test lamp illuminates between each ignition circuit terminal, which is controlled by a control module, and ground.
    • If the test lamp does not illuminate 
    1. Ignition/Vehicle OFF, remove the test lamp, disconnect the harness connectors at the control module that controls the ignition circuit and all devices that share the same ignition circuit.
    2. Test for infinite resistance between the ignition 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 ignition circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Reconnect the control module that controls the ignition circuit, ignition ON/Vehicle In Service Mode.
    5. Verify a test lamp illuminates between the ignition circuit terminal and ground.
      • If the test lamp does not illuminate, replace the control module that controls the ignition circuit.
      • If the test lamp illuminates
    6. Ignition/Vehicle OFF, reconnect the first device that shares the same ignition circuit, ignition ON/Vehicle In Service Mode.
    7. Verify a test lamp illuminates between the ignition circuit terminal and ground.
      • If the test lamp does not illuminate, replace the device that was just connected.
      • If the test lamp illuminates and there are more devices to connect, connect the next device and repeat step 6.7 until there are no more devices to connect.
    • Go to next step: If the test lamp illuminates 
  7. Ignition/Vehicle OFF, disconnect all LIN devices that share the same LIN serial data circuit, ignition ON/Vehicle In Service Mode.
    8. NOTE:

    For accurate voltage reading, disconnect the battery charger prior to performing the following test step.

  8. Test for 2 - 12 V between the LIN serial data circuit terminal and ground.
    • If less than 2 V 
    1. Ignition/Vehicle OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the serial data 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 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. Reconnect the K20 Engine Control Module, ignition ON/Vehicle In Service Mode.
    5. Test for 2 - 12 V between the LIN serial data circuit terminal and ground.
      • If less than 2 V, replace the K20 Engine Control Module.
      • If greater than 2 V, replace the LIN device that causes a current DTC to set when connected.
    • If greater than 12 V 
    1. Ignition/Vehicle OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON/Vehicle In Service Mode.
    2. Test for less than 1 V between the serial data circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Ignition/Vehicle OFF, reconnect the K20 Engine Control Module, ignition ON/Vehicle In Service Mode.
    4. Test for 2 - 12 V between the LIN serial data circuit terminal and ground.
      • If greater than 12 V, replace the K20 Engine Control Module.
      • If less than 12 V, replace the LIN device that causes a current DTC to set when connected.
    • Go to next step: If between 2 - 12 V 
  9. Replace the B110 Battery Sensor Module.
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