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Home >> Ford >> 2000 >> Contour SE, 2.5 L, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 794 (Supplemental Restraint System) >> Diagnosis And Testing >> Pinpoint Tests - Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) >> Pinpoint Test M: LFC 14/B1921 - Air Bag Diagnostic Monitor Ground Circuit Open >> Pinpoint Test M: LFC 14/DTC B1921 - Air Bag Diagnostic Monitor Ground Circuit Open

Pinpoint Test M: LFC 14/DTC B1921 - Air Bag Diagnostic Monitor Ground Circuit Open

WARNING: This page is about a different car, the 2005 Ford RV Cutaway, 2005 Ford Econoline, 2005 Ford E450 Super Duty, and 2005 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Most faults are due to connector and/or wiring concerns. Carry out thorough Inspection and Verification  before proceeding with the Pinpoint Test.
  1. M1 CHECK FOR CONTINUOUS AND ON-DEMAND DTCs 
    WARNING: Restraint system diagnostic tools are for service only. Tools must be removed prior to operating the vehicle over the road. Failure to remove restraint system diagnostic tools could result in injury and possible violation of vehicle safety standards.
    WARNING: Never probe the connectors on the air bag module. Doing so can result in air bag deployment, which can result in personal injury.
    WARNING: The safety belt pretensioner is a pyrotechnic device. Always wear safety glasses when repairing an air bag equipped vehicle and when handling a safety belt buckle pretensioner or safety belt retractor pretensioner. Never probe a pretensioner electrical connector. Doing so could result in pretensioner or air bag deployment and could result in personal injury.
    CAUTION: To avoid potential damage to the restraints control module (RCM), make sure the RCM and bracket assembly is secured to the floor pan and the SRS is depowered before either disconnecting or reconnecting the RCM electrical connectors.
    NOTE: After diagnosing or repairing an SRS, the restraint system diagnostic tools must be removed before operating the vehicle over the road.
    NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
    • Enter the following diagnostic mode on the scan tool: Retrieve/Record Continuous DTCs.
    • Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
    • Was DTC B1921 retrieved during the on-demand self test? 
    • Yes  : This is a hard fault. The fault condition is still present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to M2.
    • No  : This is an intermittent fault. The fault condition is not present at this time. GO to  M6.
  2. M2 INSPECT THE RCM MOUNTING, MOUNTING BRACKET AND MOUNTING SURFACE 
    • Key in OFF position.
    • Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Inspect the RCM retainers and RCM bracket mounting bolts and make sure they are fully seated and tightened correctly.
    • Remove the RCM. Refer to RESTRAINTS CONTROL MODULE (RCM) .
    • Visually inspect the RCM, mounting bracket and mounting surface for damage, corrosion or dirt.
    • Was a significant amount of corrosion or dirt found, or was the RCM mounting bracket attached to the mounting surface incorrectly or were the RCM retainers not fully seated and tightened correctly? 
    • Yes  : CLEAN and TIGHTEN the retainers. REPAIR the mounting surface as necessary. REINSTALL the RCM and mounting bracket to the mounting surface. GO to  M7.
    • No  : GO to M3.
  3. M3 INSTALL THE RCM AND CARRY OUT THE ON-DEMAND SELF TEST 
    • Yes  : GO to M4.
    • No  : Fault corrected. GO to  M7.
  4. M4 CHECK GROUND CIRCUIT 1203 (BK/LB) FOR HIGH RESISTANCE 
    • Key in OFF position.
    • Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Measure the resistance between RCM C310a pin 16, circuit 1203 (BK/LB), harness side and the RCM case ground.
      Fig 1: Measuring Resistance Between RCM Pin 16 And RCM Case Ground
      G03891303Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to M5.
    • No  : REPAIR circuit 1203 (BK/LB). GO to  M7.
  5. M5 CONFIRM THE RCM FAULT 
    NOTE: Make sure all restraint system diagnostic tools, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the on-demand self test. If not, erroneous DTCs will be recorded.
    • Key in OFF position.
    • Connect: RCM C310a.
    • Repower the system. Do not  prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
    • Was DTC B1892 retrieved during the on-demand self test? 
    • Yes  : INSTALL a new RCM. REFER to RESTRAINTS CONTROL MODULE (RCM) . GO to  M7.
    • No  : CHECK for causes of intermittent high resistance on circuit 1203 (BK/LB) or the chassis ground. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to  M7.
  6. M6 CHECK FOR AN INTERMITTENT FAULT 
    • Key in OFF position.
    • Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
    • Was DTC B1921 retrieved during the on-demand self test? 
    • Yes  : GO to  M2.
    • No  : CHECK for causes of intermittent high resistance on circuit 1203 (BK/LB) or the chassis ground. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to M7.
  7. M7 CHECK FOR ADDITIONAL DTCs 
    • Refer to the continuous DTCs recorded during Step  M1.
    • Were any continuous DTCs retrieved Step   M1 ? 
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