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Diagnostic Test

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read 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 DTCM DTCs.

      Did the DTC return?

      Yes 

      • Go To  2

      No 

  2. CHECK THE RDM AXLE SHAFT ACTUATOR (A196) FUSED B(+) CIRCUIT FOR AN OPEN OR SHORT 
    1. Turn the ignition off.
    2. Disconnect the RDM Axle Shaft Actuator harness connector.
    3. Turn the ignition on.
    4. Using a 12-volt test light connected to ground, check the (A196) Fused B(+) circuit at the RDM Axle Shaft Actuator harness connector.

      Does the test light illuminate brightly?

      Yes 

      • Go To  3

      No 

      • Repair the (A196) Fused B(+) circuit for an open, high resistance, or short to ground.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST .
  3. CHECK THE RDM AXLE SHAFT ACTUATOR (F946) FUSED IGNITION (RUN-START) CONTROL OUTPUT CIRCUIT FOR AN OPEN OR SHORT 
    1. Using a 12-volt test light connected to ground, check the (F946) Fused Ignition (Run-Start) Control Output circuit at the RDM Axle Shaft Actuator harness connector.

      Does the test light illuminate brightly?

      Yes 

      • Go To  4

      No 

      • Repair the (F946) Fused Ignition (Run-Start) Control Output circuit for an open or short.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST .
  4. CHECK THE RDM AXLE SHAFT ACTUATOR (Z924) GROUND CIRCUIT FOR AN OPEN 
    1. Turn the ignition off.
    2. Using a 12-volt test light connected to 12-volts, check the (Z924) Ground circuit at the RDM Axle Shaft Actuator harness connector.

      Does the test light illuminate brightly?

      Yes 

      • Go To  5

      No 

      • Repair the (Z924) Ground circuit for an open.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST .
  5. CHECK THE (D469) PRIVATE CONTROLLER AREA NETWORK (CAN) (+) CIRCUIT FOR AN OPEN 
    1. Disconnect the DTCM C1 harness connector.
    2. Measure the resistance of the (D469) PRIVATE CAN C (+) circuit between the RDM Axle Shaft Actuator harness connector and the DTCM C1 harness connector.

      Is the resistances below 3.0 Ohms?

      Yes 

      • Go To  6

      No 

      • Repair the (D469) PRIVATE CAN C (+) circuit for an open.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST .
  6. CHECK THE (D468) PRIVATE CAN C(-) CIRCUIT FOR AN OPEN 
    1. Measure the resistance of the (D468) PRIVATE CAN C (-) circuit between the RDM Axle Shaft Actuator harness connector and the DTCM C1 harness connector.

      Are the resistances below 3.0 Ohms?

      Yes 

      • Go To  7

      No 

      • Repair the (D468) PRIVATE CAN C (-) circuit for an open.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST .
  7. REPLACE THE RDM AXLE SHAFT ACTUATOR AND CHECK FOR THE DTC TO RETURN 
    1. Replace the RDM Axle Shaft Actuator in accordance with the Service Information. Refer to ACTUATOR, AXLE SHAFT, REMOVAL .
    2. Turn the ignition on.
    3. With the scan tool, erase DTCs.
    4. Test drive the vehicle in Sport Mode and verify proper operation.
    5. Turn the ignition on.
    6. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Go To  8

      No 

      • The new RDM Axle Shaft Actuator repaired the problem.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST .
  8. CHECK RELATED HARNESS CONNECTIONS 
    1. Disconnect all DTCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. 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.

    5. Reconnect all DTCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    10. With the scan tool, read DTCM DTCs.

      Did the DTC return?

      Yes 

      No 

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