LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Alfa Romeo >> 2017 >> 4C Base >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> (Occupant Restraint Controller (Orc) - Electrical Diagnostics) >> DTC Troubleshooting >> U1701-87-ECM (Engine Control Module) Node - Missing Message >> Diagnostic Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read DTCs.

      Is the DTC active?

      Yes 

      • Go To  2

      No 

      • Test complete.
  2. CHECK THE CAN LINE WIRING BETWEEN THE ECM AND THE ORC 
    1. Check the CAN connections and in particular that there are no open or short circuit problems.
    2. Check that the connector is correctly connected to the control units and there are no faulty connections in the intermediate joint.

      Was there a fault detected?

      Yes 

      • Reconnect the connectors or repair circuit faults according to service procedures.

      No 

      • Go To  3
  3. TEST THE POWER AND GROUND CIRCUITS TO THE ECM AND THE ORC 
    1. Check the related power and ground circuits the ECM and the ORC.

      Was there a fault found in any of the power or ground circuits?

      No 

      • Go To.

        Refer to  4.

      Yes 

      • Repair affected circuits according to service procedures.
  4. CHECK ECM AND ORC OPERATION 
    1. Check the operation of both modules.

      Was a fault detected?

      Yes 

      • Replace the affect module.
scientia non olet · About LEMON Manuals