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Home >> Mercury >> 2010 >> Milan Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 1110 (Supplemental Inflatable Restraint System) >> Diagnostic Tests >> Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) >> Pinpoint Tests >> Pinpoint Test I: LFC 51/DTC B2434 - Drivers Seat Belt Buckle Switch Circuit Short to Ground >> Pinpoint Test I: DTC B2434 - Drivers Seat Belt Buckle Switch Circuit Short To Ground

Pinpoint Test I: DTC B2434 - Drivers Seat Belt Buckle Switch Circuit Short To Ground

WARNING: This page is about a different car, the 2008 Ford RV Cutaway, 2008 Ford Econoline, 2008 Ford E450 Super Duty, and 2008 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: Never probe the electrical connectors on safety belt buckle/retractor pretensioners or adaptive load limiting retractors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors, which increases the risk of serious personal injury or death.
NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
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: Supplemental restraint system (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: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
  1. I1 CHECK FOR CONTINUOUS AND ON-DEMAND DTCs 
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs
    • Was on-demand DTC B2434 retrieved? 
    1. 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  I2.
    2. NO  : This is an intermittent fault when present as a continuous memory DTC only (DTC not retrieved on-demand). The fault condition is not present at this time. Go to  I5.
  2. I2 CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH FOR A SHORT TO GROUND 
    NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.
    • Key in OFF position.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • Disconnect: Driver Safety Belt Buckle Switch C3338
    • Repower the SRS. Do not  prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs
    • DIAGNOSTIC TIP:  When viewing on-demand DTCs with the driver safety belt buckle switch disconnected, a open circuit fault would normally be retrieved.
    • Did the driver safety belt buckle switch on-demand DTC change from indicating B2434 to B2691? 
    1. YES  : INSTALL a new driver safety belt buckle assembly. REFER to SAFETY BELT SYSTEM article. Go to  I6.
    2. NO  : Go to  I3.
  3. I3 CHECK CIRCUIT 85 (BN/LB) FOR A SHORT TO GROUND BETWEEN THE RCM AND DRIVER SAFETY BELT BUCKLE SWITCH 
    • Key in OFF position.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • Disconnect: RCM C310a and C310b
    • Fig 1: Checking Circuit 85 (BN/LB) For A Short To Ground Between RCM & Driver Safety Belt Buckle Switch
      GF0044532Courtesy of FORD MOTOR CO.
    • Measure the resistance between driver safety belt buckle switch C3338-4, circuit 85 (BN/LB), harness side and ground.
    • Is the resistance greater than 10,000 ohms? 
    1. YES  : Go to  I4.
    2. NO  : REPAIR circuit 85 (BN/LB). Go to  I6.
  4. I4 CONFIRM THE RCM FAULT 
    NOTE: Make sure all restraint system components and the RCM electrical connectors are connected before carrying out the on-demand self test. If not, erroneous DTCs will be recorded.
    • Connect: Driver Safety Belt Buckle Switch C3338
    • Connect: RCM C310a and C310b
    • Repower the SRS. Do not  prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs
    • Was on-demand DTC B2434 retrieved? 
    1. YES  : INSTALL a new RCM and CARRY OUT programmable module installation (PMI). REFER to Restraints Control Module (RCM) . Go to  I6.
    2. NO  : In the process of diagnosing the fault, the fault condition has become intermittent. CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of any electrical connectors that were disconnected. Go to  I5.
  5. I5 CHECK FOR AN INTERMITTENT FAULT 
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs
    • Was on-demand DTC B2434 retrieved? 
    1. YES  : This is a hard fault. The fault condition is now 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  I2.
    2. NO  : CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. 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.  REPAIR any intermittent wiring, terminal or connectors concerns found. Go to  I6.
  6. I6 CHECK FOR ADDITIONAL SRS DTCs 
    • Key in OFF position.
      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.
    • Reconnect all SRS components (if previously disconnected).
    • Key in ON position.
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs
    • Enter the following diagnostic mode on the diagnostic tool: Clear all RCM Continuous Memory DTCs
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/RCM
    • Are any RCM DTCs retrieved indicating a fault? 
    1. YES  : Do not clear any DTCs until all DTCs have been resolved. Go to Supplemental Restraint System (SRS) DTC Chart  for pinpoint test direction.
    2. NO  : PROVE OUT the SRS. REPAIR is complete. RETURN the vehicle to the customer.