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Home >> Alfa Romeo >> 2017 >> Giulia Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> (Active Cruise Control Module (Acc) - Electrical Diagnostics) >> DTC Troubleshooting >> C1439-86-Engine Torque Signals From Engine Control Module (ECM) - Signal Invalid >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read Adaptive Cruise Control (ACC) DTCs and record on the repair order.
    2. With the scan tool, erase ACC Module DTCs.
    3. Turn the ignition off for ten seconds, then start the engine.
    4. With the scan tool, read ACC DTCs.

      Did the DTC return?

      Yes 

      • Go To  2

      No 

  2. CHECK THE PCM FOR DTCS 
    1. With the scan tool, read Powertrain Control Module (PCM) DTCs and record on the repair order.
    2. Record the DTC information on the repair order.

      Are there any PCM DTCs set?

      Yes 

      • Repair the DTC(s) in the PCM. Refer to DTC INDEX .

      No 

      • Go To  3
  3. CHECK RELATED WIRING AND HARNESS CONNECTIONS 
    1. Turn the ignition off.
    2. Check the related component and module power supply and ground circuits.
    3. Disconnect harness connectors between the ACC Module and the PCM.
    4. Disconnect all related in-line harness connections (if equipped).
    5. Disconnect the related component harness connectors.
    6. 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.

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

      Did the DTC return?

      Yes 

      No