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Home >> Ford >> 2018 >> Mustang EcoBoost, 2D Convertible, Standard Trans >> Repair and Diagnosis >> Restraints >> Restraints Control Systems >> RCM Guided Routine Testing -- (Pinpoint Tests A - Ax) >> Pinpoint Tests >> PINPOINT TESTs AP: OCSM Lost Communication with RCM >> Possible Causes
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Possible Causes

WARNING: Do not handle, move or change the original horizontal mounting position of the RCM while the RCM is connected and the ignition switch is ON. Failure to follow this instruction may result in the accidental deployment of the Safety Canopy® and cause serious personal injury or death.
NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.
NOTE: SRS components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.
NOTE: Always make sure the correct OCSM component is being installed. Parts released for other vehicles may not be compatible even if they appear physically similar. Check the part number listed in the Ford parts catalog to make sure the correct component is being installed. If an incorrect OCSM component is installed, DTCs may set.
  1. AP1: CHECK THE COMMUNICATION NETWORK 
    WARNING: Before beginning any service procedure in this article, refer to Safety Warnings in General Information article. Failure to follow this instruction may result in serious personal injury. Refer to Pyrotechnic Device Health and Safety Precautions.
    • Ignition ON, engine OFF.
    • Press the Read Vehicle Information button to view the results of the modules communicating on the network.
    • Retrieve the continuous memory DTCs.
    • Does the RCM pass the network test? 
    Yes No
    Go to  AP2. DIAGNOSE the scan tool does not communicate with the RCM. Refer to Module Communications Network article
  2. AP2: CHECK THE OCSM CMDTCS 
    • Carry out the OCS self-test.
    • Clear the OCS DTCs.
    • Wait 10 seconds.
    • Carry out the OCS self-test.
    • Is DTC U0151:00 retrieved again? 
    Yes No
    Go to  AP3. The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.
  3. AP3: CHECK FOR RCM VOLTAGE RELATED DTCS 
    • Carry out the RCM self-test.
    • Is DTC U3003:16 or U3003:17 recorded? 
    Yes No
    REFER to the RCM - Restraint Control Module  DTC Chart. Go to  AP4.
  4. AP4: CHECK FOR OCSM VOLTAGE RELATED DTCS 
    • Carry out the OCS self-test.
    • Check the recorded DTCs from the OCSM self-test.
    • Is DTC U3003:16 or U3003:17 recorded? 
    Yes No
    REFER to the RCM - Restraint Control Module  DTC Chart. Go to  AP5.
  5. AP5: CHECK FOR DTC U0151:00 SET IN OTHER MODULES 
    • Ignition ON, engine OFF.
    • Press the Read Vehicle Information button to view the results of the modules CMDTCs.
    • Retrieve the continuous memory DTCs.
    • Is DTC U0151:00 set in any other module in addition to the OCSM? 
    Yes No
    Go to  AP6. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
    If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.
  6. AP6: CHECK FOR CORRECT RCM OPERATION 
    • Ignition OFF.
    • If not previously directed to do so, depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering in the General Procedures of Supplemental Restraint System article.
    • Disconnect and inspect the RCM connectors (if not previously disconnected).
    • Repair:
      • corrosion (install new connector or terminal - clean module pins)
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary
    • RCM_A connector connected. (C310A) Make sure it seats and latches correctly. Make sure the connector engages the Connector Position Assurance (CPA) lever/lock.
    • RCM_B connector connected. (C310B) Make sure it seats and latches correctly. Make sure the connector engages the Connector Position Assurance (CPA) lever/lock.
    • Repower the SRS. Refer to Supplemental Restraint System (SRS) Repowering in the General Procedures of Supplemental Restraint System article.
    • Is the concern still present? 
    Yes No
    INSTALL a new RCM.
    CHECK OASIS for any applicable Technical Service Bulletins TSBs.
    If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions.
    If no TSBs address this concern, INSTALL a new RCM. REFER to the appropriate Removal and Installation procedure in Supplemental Restraint System article.
    ORDER a replacement RCM and INCLUDE the RVC on the form.
    If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.    		 The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
    If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.
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