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Diagnostic Test

WARNING: This page is about a different car, the 2021 Chrysler 300. 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 (F348) SMART POWER RELAY FEED CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Remove the Front Axle Disconnect (FAD) Relay.
    3. Disconnect the Drivetrain Control Module (DTCM) harness connector.
    4. Connect a jumper wire between the (F348) Smart Power Relay Feed circuit and ground.
    5. Turn the ignition on.
    6. With a 12-volt test light connected to 12 volts, check the (F348) Smart Power Relay Feed circuit.
      NOTE:

      The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

      Does the test light illuminate brightly?

      Yes 

      • Go To  3

      No 

      • Repair the (F348) Smart Power Relay Feed circuit for an open or high resistance.
      • Perform the DTCM VERIFICATION TEST. Refer to DTCM VERIFICATION TEST  .
  3. 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  .