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Circuit/System Testing

Test A

  1. Ignition OFF and all vehicle systems OFF. Disconnect the connector at the appropriate B11 Suspension 4 Corner Leveling System Position Sensor:
    • DTC C103C = B11LF Front Suspension 4 Corner Leveling System Position Sensor - Left
    • DTC C103D = B11LR Rear Suspension 4 Corner Leveling System Position Sensor - Left
    • DTC C103E = B11RF Front Suspension 4 Corner Leveling System Position Sensor - Right
    • DTC C103F = B11RR Rear Suspension 4 Corner Leveling System Position Sensor - Right
  2. Test for less than 10 Ω between the low reference circuit terminal 2 and ground.
    • If 10 Ω or greater 
    1. Test the appropriate circuit for an open/high resistance:
      • DTC C103C = Circuit 1206
      • DTC C103D = Circuit 1209
      • DTC C103E = Circuit 1212
      • DTC C103F = Circuit 1215
      • If an open/high resistance is found, repair the circuit fault.
      • Go to next step: If an open/high resistance is not found
    2. Replace the K5 Automatic Level Control Module.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON.
  4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 1 and ground.
    • If less than 4.8 V 
    1. Test the appropriate circuit for a short to ground:
      • DTC C103C = Circuit 1205
      • DTC C103D = Circuit 1208
      • DTC C103E = Circuit 1211
      • DTC C103F = Circuit 1214
      • If a short to ground is found, repair the circuit fault.
      • Go to next step: If a short to ground is not found
    2. Test the appropriate circuit for an open/high resistance:
      • DTC C103C = Circuit 1205
      • DTC C103D = Circuit 1208
      • DTC C103E = Circuit 1211
      • DTC C103F = Circuit 1214
      • If an open/high resistance is found, repair the circuit fault.
      • Go to next step: If an open/high resistance is not found
    3. Replace the K5 Automatic Level Control Module.
    • If greater than 5.2 V 
    1. Test the appropriate circuit for a short to voltage:
      • DTC C103C = Circuit 1205
      • DTC C103D = Circuit 1208
      • DTC C103E = Circuit 1211
      • DTC C103F = Circuit 1214
      • If a short to voltage is found, repair the circuit fault.
      • Go to next step: If a short to voltage is not found
    2. Replace the K5 Automatic Level Control Module.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Test for less than 1 V between the signal circuit terminal 3 and ground.
    • If 1 V or greater 
    1. Test the appropriate circuit for a short to voltage:
      • DTC C103C = Circuit 1207
      • DTC C103D = Circuit 1210
      • DTC C103E = Circuit 1213
      • DTC C103F = Circuit 1216
      • If a short to voltage is found, repair the circuit fault.
      • Go to next step: If a short to voltage is not found
    2. Replace the K5 Automatic Level Control Module.
    • Go to next step: If less than 1 V 
  6. Ignition OFF. Disconnect the connector at the K5 Automatic Level Control Module.
  7. Test for infinite resistance between signal circuit terminal 3 and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  8. Test for less than 2 Ω between signal circuit terminal 3 and the other end of the circuit.
    • If greater than 2 Ω 

      Repair the open/high resistance on the circuit.

    • Go to next step: If less than 2 Ω 
  9. Test or replace the appropriate B11 Suspension 4 Corner Leveling System Position Sensor.
  10. Operate vehicle under the Coniditions for Running the DTC.
  11. Verify DTCs C103C, C103D, C103E, or C103F do not set.
    • If any of the DTCs set 

      Replace the K5 Automatic Level Control Module.

    • Go to next step: If none of the DTCs set 
  12. A fault is not currently present and may be an intermittent condition.

Test B

  1. Verify that all B11 Suspension 4 Corner Leveling System Position Sensors are installed properly and are not damaged.
    • If all sensors are not installed properly or damage is found 
    1. Reinstall B11 Suspension 4 Corner Leveling System Position Sensors properly or replace as necessary.
    2. Verify DTCs do not reset.
      • If DTCs reset, replace the K5 Automatic Level Control Module.
      • Go to next step: If DTCs do not reset
    3. All OK.
    • Go to next step: If all sensors are installed properly and no damage is found 
  2. Clear DTCs and operate the vehicle under Condition for Running the DTC.
  3. Verify DTCs do not reset.
    • If any DTCs reset 

      Replace the appropriate B11 Suspension 4 Corner Leveling System Position Sensor

    • Go to next step: If DTCs do not reset 
  4. A fault is not currently present and may be an intermittent condition.

Test C

  1. Ignition ON.
  2. Adjust vehicle ride height to within specification using Inflate/Deflate functions in scan tool. Refer to: Trim Height Inspection , and Trim Height Specifications
  3. Perform Automatic Level Control Trim Height Learn procedure. Refer to: Automatic Level Control Trim Height Learn 
  4. Clear DTCs.
  5. Verify DTCs do not reset.
    • If DTCs reset 

      Replace the K5 Automatic Level Control Module

    • Go to next step: If DTCs do not reset 
  6. All OK.
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