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Circuit/System Testing

Only DTC U0125 is set

  1. Ignition OFF and all vehicle systems OFF. Disconnect the harness connectors at the B119 multi-axis acceleration sensor. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 1 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 ignition circuit terminal 4 and ground.
    • If the test lamp does not illuminate 

      Repair the open/high resistance in the circuit between the splice and the B119 multi-axis acceleration sensor.

    • If the test lamp illuminates 
  5. Test for less than 130 Ω between the serial data circuits terminal 2 and 3.
    • If 130 Ω or greater 
    1. Ignition OFF, disconnect the harness connectors at the B99 steering angle sensor.
    2. Test for less than 2 Ω in each serial data circuit terminals listed below end to end.
      • B119 multi-axis acceleration sensor terminal 2 and the B99 steering angle sensor terminal 2
      • B119 multi-axis acceleration sensor terminal 3 and the B99 steering angle sensor terminal 4
      • If greater than 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the B99 steering angle sensor.
    • If less than 130 Ω 
  6. Replace the B119 multi-axis acceleration sensor.

Only DTC U0126 is set

  1. Ignition OFF and all vehicle systems OFF. Disconnect the harness connectors at the B99 steering angle sensor. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 6 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 ignition circuit terminal 5 and ground.
    • If the test lamp does not illuminate 

      Repair the open/high resistance in the circuit between the splice and the B99 steering angle sensor.

    • If the test lamp illuminates 
  5. Replace the B99 steering angle sensor.

DTC U0074

  1. Ignition OFF and all vehicle systems OFF. Disconnect the harness connectors at the B99 steering angle sensor. It may take up to 2 minutes for all vehicle systems to power down.
  2. Ignition ON.
  3. Verify a test lamp illuminates between the ignition circuit terminal 5 and ground.
    • If the test lamp does not illuminate 
    1. Ignition OFF, disconnect the harness connectors at the B119 multi-axis acceleration sensor, ignition ON.
    2. Verify a test lamp illuminates between the ignition circuit and ground.
      • If the test lamp illuminates, replace the B119 multi-axis acceleration sensor.
      • If the test lamp does not illuminate
    3. Ignition OFF, disconnect the harness connectors at the K17 electronic brake control module.
    4. Test for infinite resistance between the ignition circuit and ground.
      • If less than infinite resistance, repair the short ground on the circuit.
      • If infinite resistance
    5. Test for less than 2 Ω in the ignition circuit end to end between the B99 steering angle sensor and the K17 electronic brake control module terminal 32.
      • If greater than 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K17 electronic brake control module.
    • If the test lamp illuminates 
  4. Test for less than 4.5 V between each serial data circuit listed below and ground.
    • Terminal 1
    • Terminal 3
    • If 4.5 V or greater 
    1. Ignition OFF, disconnect the harness connectors at the K17 electronic brake control module.
    2. Test for less than 1 V between each serial data circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K17 electronic brake control module.
    • If less than 4.5 V 
  5. Test for less than 4.5 V between each serial data circuit listed below and ground.
    • Terminal 2
    • Terminal 4
    • If 4.5 V or greater 
    1. Ignition OFF, disconnect the harness connectors at the B119 multi-axis acceleration sensor.
    2. Test for less than 1 V between each serial data circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the B119 multi-axis acceleration sensor.
    • If less than 4.5 V 
  6. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
  7. Test for greater than 100 Ω between each serial data circuits listed below and ground.
    • Terminal 1
    • Terminal 3
    • If 100 Ω or less 
    1. Ignition OFF, disconnect the harness connectors at the K17 electronic brake 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, replace the K17 electronic brake control module.
    • If greater than 100 Ω 
  8. Test for greater than 100 Ω between each serial data circuit listed below and ground.
    • Terminal 2
    • Terminal 4
    • If 100 Ω or less 
    1. Ignition OFF, disconnect the harness connectors at the B119 multi-axis acceleration sensor.
    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, replace the B119 multi-axis acceleration sensor.
    • If greater than 100 Ω 
  9. Test for 110-130 Ω between the serial data circuits terminal 1 and 3.
    • If less than 110 Ω 
    1. Ignition OFF, disconnect the harness connectors at the K17 electronic brake control module.
    2. Test for infinite resistance between the serial data circuits.
      • If less than infinite resistance, repair the short between the circuits.
      • If infinite resistance, replace the K17 electronic brake control module.
    • If greater than 130 Ω 
    1. Ignition OFF, disconnect the harness connectors at the K17 electronic brake control module.
    2. Test for less than 2 Ω in each serial data circuit terminals listed below end to end.
      • B99 steering angle sensor terminal 1 and K17 electronic brake control module terminal 24
      • B99 steering angle sensor terminal 3 and K17 electronic brake control module terminal 37
      • If greater than 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K17 electronic brake control module.
    • If between 110-130 Ω 
  10. Test for 110-130 Ω between the serial data circuits terminal 2 and 4.
    • If less than 110 Ω 
    1. Ignition OFF, disconnect the harness connectors at the B119 multi-axis acceleration sensor.
    2. Test for infinite resistance between the serial data circuits.
      • If less than infinite resistance, repair the short between the circuits.
      • If infinite resistance, replace the B119 multi-axis acceleration sensor.
    • If greater than 130 Ω 
    1. Ignition OFF, disconnect the harness connectors at the B119 multi-axis acceleration sensor.
    2. Test for less than 2 Ω in each serial data circuit terminals listed below end to end.
      • B99 steering angle sensor terminal 2 and B119 multi-axis acceleration sensor terminal 2
      • B99 steering angle sensor terminal 4 and B119 multi-axis acceleration sensor terminal 3
      • If greater than 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the B119 multi-axis acceleration sensor.
    • If between 110-130 Ω 
  11. Replace the B99 steering angle sensor.
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