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Diagnostic Test

WARNING: This page is about a different car, the 2021 Jeep Grand Cherokee L. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR DTC TO RETURN 
    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 SCCM connectors may cause the DTC to set.

    NOTE:

    If steering system service has been performed and the Steering Angle Sensor (SAS) has been installed incorrectly, this DTC may set. Refer to the Service Information to verify repairs have been performed correctly.

    1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
    2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
    3. With the scan tool, erase all DTCs.
    4. Turn the ignition off for a minimum of 10.0 seconds.
    5. Turn the ignition on.
    6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read DTCs.

    Did the DTC return?

    Yes 

    WARNING:

    Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

    WARNING:

    Do not place an intact non-deployed airbag face down on a hard surface, the airbag propels into the air if accidentally deployed. Failure to follow these instructions may result in possible serious or fatal injury.

    • 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 BSCM VERIFICATION TEST. Refer to BSCM VERIFICATION TEST .
  2. CHECK FOR STEERING COLUMN CONTROL MODULE (SCCM) OR COMMUNICATION RELATED DTCS 
    1. Refer to the recorded DTCs.

      Are there any SCCM or Communication related DTCs active?

      Yes 

      • Perform the appropriate diagnostic procedures before continuing with this test. Refer to DIAGNOSTIC CODE INDEX .

      No 

      • Go To  3
  3. REPLACE THE STEERING ANGLE SENSOR (SAS) AND TEST FOR DTCS 
    NOTE:

    The Steering Angle Sensor (SAS) is internal to the Steering Column Control Module (SCCM).

    1. Replace the Steering Column Control Module (SCCM) in accordance with the Service Information. Refer to MODULE, STEERING COLUMN CONTROL (SCCM), REMOVAL AND INSTALLATION .
      1. Connect the component and Electronic Control Unit (ECU) harness connectors.
      2. Turn the ignition on.
      3. With the scan tool, erase DTCs.
      4. Using the Environmental Data or When Monitored Conditions above, operate the vehicle within the conditions that set the DTC.
      WARNING:

      To avoid possible serious or fatal injury, check brake capability is available before road testing.

    2. Test drive the vehicle by turning the vehicle left and right in a curving manner at a velocity above 50 km/h (30 mph).
    3. With the scan tool, read the DTCs.

      Did the DTC return?

      Yes 

      • Go To  4

      No 

      • Replacing the faulty component repaired the fault.
  4. CHECK RELATED HARNESS CONNECTIONS 
    1. Turn the ignition off.
    2. Disconnect the BSCM harness connector.
    3. Disconnect all related in-line harness connections (if equipped).
    4. Disconnect the related component harness connectors.
    5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Perform a terminal drag test on each connector terminal to verify proper terminal tension.

      Repair any conditions that are found.

    6. Connect the BSCM harness connector. Be certain that the harness connector is fully seated and the connector lock is fully engaged.
    7. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. Connect the related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    9. With the scan tool, erase DTCs.
      WARNING:

      To avoid possible serious or fatal injury, check brake capability is available before road testing.

    10. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    11. With the scan tool, read BSCM DTCs.

      Did the DTC return?

      Yes 

      No 

      • The wiring or poor connection problem has been repaired.
      • Perform the BSCM VERIFICATION TEST. Refer to BSCM VERIFICATION TEST .
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