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Home >> Jeep >> 2021 >> Renegade Trailhawk >> Repair and Diagnosis (Single Page) >> Body & Frame >> Towing Systems >> (Trailer Tow Module- Electrical Diagnostics) >> DTC Troubleshooting >> U1700-86: BCM Body Computer Module - Signal Invalid >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read Trailer Tow Module (TTM) 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 TTM DTCs.

      Did the DTC return?

      Yes 

      • Go To  2

      No 

  2. VERIFY IF THIS DTC SET IN OTHER MODULES 
    1. Turn the ignition on.
    2. With the scan tool, read active DTCs.

      Are any other modules on the CAN BUS reporting this DTC?

      Yes 

      • Replace and program the Module that set this DTC in accordance to the Service Information. Perform its respective verification test.
      • Perform the verification test for the replaced modules. If a verification test does not exist, perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  3
  3. CHECK RELATED HARNESS CONNECTIONS 
    1. Disconnect all BCM 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 BCM 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 TTM DTCs.

      Did the DTC return?

      Yes 

      No