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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    NOTE:

    Before proceeding with the diagnostic procedure, verify that the connections are properly made, seated and verify proper pin terminal tension. A loose connection at any of the SCM connectors may cause the DTC to set.

    1. With the scan tool, read Body Control Module (BCM) DTCs and record on the repair order.
    2. Record the Environmental Data.
    3. With the scan tool, erase DTCs.
    4. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    5. With the scan tool, read BCM DTCs.

      Did the DTC return?

      Yes 

      • Go To  2

      No 

      • Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  2. CHECK THE STEERING CONTROL MODULE (SCM) OPERATION 
    1. Turn the ignition on.
    2. Using the scan tool, view the SCM Data while actuating the Horn Switch and Speed Control Switch functions on and off.

      Does the SCM Data match the on and off states of the Horn Switch and Speed Control Switch functions?

      Yes 

      No 

      • Go To  3
  3. CHECK FOR OTHER DTCS 
    1. With the scan tool, read DTCs and record on the repair order

      Are there any active voltage related DTC's on any related modules (PDC, CLUSTER, etc)?

      Yes 

      • Diagnose and Repair the voltage related concern via the procedure for the DTC given for that related module.

      No 

      • Go To  4
  4. CHECK FOR VOLTAGE ON THE (A929) FUSED B (+) CIRCUIT AT THE RIGHT STEERING WHEEL SWITCH HARNESS CONNECTOR 
    1. Turn the ignition off.
    2. Disconnect the Right Steering Wheel Switch (Speed Control Switch) harness connector.
    3. Turn the ignition on.
    4. Measure the voltage on the (A929) Fused B (+) circuit at the Right Steering Wheel Switch harness connector.

      Is there any voltage present?

      Yes 

      • Go To  7

      No 

      • Go To  5
  5. CHECK THE (A929) FUSED B (+) CIRCUIT FOR AN OPEN 
    1. Turn the ignition off.
    2. Disconnect the SCM C6 harness connector.
    3. Measure the resistance on the (A929) Fused B (+) circuit between the Right Steering Wheel Switch harness connector and SCM C6 harness connector.

      Is the resistance above 3.0 Ohms?

      Yes 

      • Repair the open in the (A929) Fused B (+) circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  6
  6. CHECK THE (A929) FUSED B (+) CIRCUIT FOR A SHORT TO GROUND 
    1. Check for continuity between ground and the (A929) Fused B (+) circuit at the Right Steering Wheel Switch harness connector.

      Is there any continuity between ground and the (A929) Fused B (+) circuit?

      Yes 

      • Repair the short to ground in the (A929) Fused B (+) circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

  7. CHECK THE RESISTANCE OF THE (Z911) GROUND CIRCUIT AT THE RIGHT STEERING WHEEL SWITCH HARNESS CONNECTOR 
    1. Turn the ignition off.
    2. Measure the resistance on the (Z911) Ground circuit between ground and the Right Steering Wheel Switch harness connector.

      Is the resistance above 3.0 Ohms?

      Yes 

      • Go To  8

      No 

      • Go To  9
  8. CHECK THE (Z911) GROUND CIRCUIT FOR AN OPEN 
    1. Disconnect the SCM C6 harness connector.
    2. Measure the resistance on the (Z911) Ground circuit between the Right Steering Wheel Switch harness connector and SCM C6 harness connector.

      Is the resistance above 3.0 Ohms?

      Yes 

      • Repair the open in the (Z911) Ground circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

  9. CHECK THE (A929) FUSED B(+) CIRCUIT OPEN OR SHORTED TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the Steering Control Module C3 harness connector.
    3. Turn the ignition on.
    4. Measure the voltage of the (A929) Fused B(+) circuit.

      Is battery voltage present?

      Yes 

      • Go To  10

      No 

      • Repair the (A929) Fused B(+) circuit for an open, short to ground or high resistance. Inspect the related fuse. If the fuse is open, check the circuit for a short to ground.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  10. CHECK THE (A902) FUSED B(+) CIRCUIT OPEN OR SHORTED TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the Steering Control Module C2 harness connector.
    3. Turn the ignition on.
    4. Measure the voltage of the (A929) Fused B(+) circuit.

      Is battery voltage present?

      Yes 

      • Go To  11

      No 

      • Repair the (A902) Fused B(+) circuit for an open, short to ground or high resistance. Inspect the related fuse. If the fuse is open, check the circuit for a short to ground.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  11. CHECK FOR VOLTAGE ON THE (D506) LIN BUS CIRCUIT 
    1. Turn the ignition off.
    2. Disconnect the Right Steering Wheel Switch (Speed Control Switch) harness connector.
    3. Turn the ignition on.
    4. Measure the voltage on the (D506) LIN Bus circuit at the Right Steering Wheel Switch harness connector.

      Is there any voltage present?

      Yes 

      • Go To  12

      No 

      • Go To  13
  12. CHECK THE (D506) LIN BUS CIRCUIT FOR A SHORT TO VOLTAGE 
    1. Measure the voltage on the (D506) LIN Bus circuit at the Right Steering Wheel Switch harness connector.

      Is the voltage greater than 10.0 volts?

      Yes 

      • Repair the short to voltage on the (D506) LIN Bus circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

  13. CHECK THE (D506) LIN BUS CIRCUIT FOR A SHORT TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the SCM C6 harness connector.
    3. Check for continuity between ground and the (D506) LIN Bus circuit at the Right Steering Wheel Switch (Speed Control Switch) harness connector.

      Is there continuity between ground and the (D506) LIN Bus circuit?

      Yes 

      • Repair the short to ground on the (D506) LIN Bus circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  14
  14. CHECK THE (D506) LIN BUS CIRCUIT FOR AN OPEN 
    1. Measure the resistance on the (D506) LIN Bus circuit between the Right Steering Wheel Switch (Speed Control Switch) harness connector and SCM C6 harness connector.

      Is the resistance above 3.0 Ohms?

      Yes 

      • Repair the open in the (D506) LIN Bus circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No