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Home >> Ford >> 2018 >> Mustang EcoBoost, 2D Convertible, Standard Trans >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> RCM Guided Routine Testing -- (Pinpoint Tests AXA - Ja) >> Pinpoint Tests >> Pinpoint Tests BI: Ignition Status - Run/Start Input Concern >> Possible Causes
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Possible Causes

WARNING: Incorrect repair techniques or actions can cause an accidental SRS deployment. Never compromise or depart from these instructions. Failure to precisely follow all instructions could result in serious personal injury from an accidental deployment.
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: Only disconnect or reconnect SRS components 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 SRS 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 SRS component is installed, DTCs may set.
NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
Fig 1: Extended Power Module Connector (C2518)
G12974407Courtesy of FORD MOTOR CO.
CIRCUIT AND PIN DESCRIPTION

Circuit Pin
IGN START/RUN-B (Ignition Start/Run - B) - CBP19 4 (BROWN/WHITE)
  1. BI1: CHECK FOR DTC U3003:16 AND U3003:17 
    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.
    NOTE: Diagnose all network-related (lost communication) DTCs first.
    • Ignition ON, engine OFF.
    • Carry out the BECMB self-test.
    • Is DTC U3003:16 or U3003:17 retrieved DTC during the self-test? 
    Yes No
    REFER to the DTC INDEX Go to  BI2.
  2. BI2: RETRIEVE BECMB DTCS 
    • Ignition ON, engine OFF.
    • Carry out the BECMB self-test.
    • Is DTC B1142:62 or B13BF:12 retrieved during self-test? 
    Yes No
    This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test.
    Go to  BI3.    		 The fault is intermittent.
    Go to  BI7.
  3. BI3: RETRIEVE BCM DTCS 
    • Are any ignition-related BCM DTCs retrieved during self-test? 
    Yes No
    DIAGNOSE and REPAIR the BCM DTCs. CLEAR the BECMB DTCs and REPEAT the BECMB self-test.
    If DTC B1142:62 or B13BF:12 is retrieved during self-test,
    Go to  BI4.    		 Key in OFF position.
    If no RCM DTCs were retrieved, the DTCs may have been triggered by aggressive driving or rough road conditions. INFORM the customer that aggressive driving conditions or rough road conditions can set these DTCs. RETURN the vehicle to the customer.
    Go to  BI4.
  4. BI4: CHECK THE BECMB IGNITION INPUT CIRCUIT FOR VOLTAGE 
    • Ignition OFF.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering in Supplemental Restraint System article.
    • BECMB connector disconnected. (C2518)
    • Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Repowering in Supplemental Restraint System article.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) BECMB (C2518) Connector, Harness Side (-)
      IGN START/RUN-B - CBP19 (BROWN/WHITE) - Pin 4 Ground
    • Is the voltage greater than 11 volts? 
    Yes No
    Go to  BI5. VERIFY that BCM fuse 35 (5A) is OK. If OK, REPAIR the open circuit. If not OK, REFER to the OEM Wiring Diagrams article to identify the possible causes of the circuit short.
    Go to  BI8.
  5. BI5: CHECK THE BECMB IGNITION INPUT CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • Remove BCM fuse 19 (7.5A).
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) BECMB (C2518) Connector, Harness Side (-)
      IGN START/RUN-B - CBP19 (BROWN/WHITE) - Pin 4 Ground
    • Is any voltage present? 
    Yes No
    REPAIR the circuit.
    Go to  BI8.    		 TURN OFF the ignition. INSTALL BCM fuse required.
    Go to  BI6.
  6. BI6: CONFIRM THE BECMB FAULT 
    NOTE: Make sure all OCSM components, restraint system sensor electrical connectors and the RCM electrical connectors are connected before carrying out the self-test. If not, DTCs are recorded.
    • Ignition OFF.
    • Prior to reconnecting any previously disconnected SRS component:
      • inspect connector(s) (including any inline connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
      • inspect wire harness for any damage, pinched, cut or pierced wires.
      • repair any concerns found.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering in Supplemental Restraint System article.
    • BECMB connector connected. (C2518) (if previously disconnected).
    • Repower the SRS. REFER to the Supplemental Restraint System (SRS) Repowering in the General Procedures portion of Supplemental Restraint System article.
    • Ignition ON, engine OFF.
    • Carry out the BECMB self-test.
    • Is the original DTC retrieved during self-test? 
    Yes No
    CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new BECMB.
    Go to  BI8.    		 In the process of diagnosing the fault, the fault condition has become intermittent. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test.
    Go to  BI7.
  7. BI7: CHECK FOR AN INTERMITTENT FAULT 
    • Ignition OFF.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering in Supplemental Restraint System article.
    • BECMB connector disconnected. (C2518)
    • Prior to reconnecting any previously disconnected SRS component:
      • inspect connector(s) (including any inline connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
      • inspect wire harness for any damage, pinched, cut or pierced wires.
      • repair any concerns found.
    • BECMB connector connected. (C2518)
    • Repower the SRS. REFER to the Supplemental Restraint System (SRS) Repowering in the General Procedures portion of Supplemental Restraint System article
    • Ignition ON, engine OFF.
    • Carry out the BECMB self-test.
    • Is DTCs B1142:62 or B13BF:12 retrieved during self-test? 
    Yes No
    The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the self-test.
    Go to  BI3.    		 CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition frequently. ACTIVATE other system in the same wire harness. Do not install any new SRS components at this time.
    Install SRS components only when directed to do so in the pinpoint test.
    Go to  BI8.
  8. BI8: CHECK FOR ADDITIONAL SRS DIAGNOSTIC TROUBLE CODES (DTCS) 
    WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
    • Ignition OFF.
    • Reconnect all SRS components (if previously disconnected).
    • If previously directed to depower the SRS, repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Repowering in Supplemental Restraint System article.
    • Ignition ON, engine OFF.
    • Clear the RCM DTCs.
    • Ignition OFF.
    • Ignition ON, engine OFF.
    • Wait 10 seconds.
    • Carry out the RCM self-test.
    • If equipped with an OCSM, carry out the OCSM self-test.
    • Carry out the OCS self-test.
    • If equipped with an BECMB, carry out the BECMB self-test.
    • Carry out the BECMB self-test.
    • Are any RCM, OCSM and/or BECM-B DTCs retrieved on-demand during self-test? 
    Yes No
    Do not clear any DTCs until all DTCs have been resolved. REFER to the DTC INDEX RCM OCSM or BECMB DTC Chart. The repair is complete. RETURN the vehicle to the customer.
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