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Home >> Mercury >> 2010 >> Milan Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 1014 (Supplemental Inflatable Restraint System) >> Diagnostic Tests >> Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) >> Pinpoint Test - Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) >> Pinpoint Test N: DTC B2691 - Seat Belt Buckle Switch Circuit Fault, Front Driver's Side >> Pinpoint Test N: DTC B2691 - Seat Belt Buckle Switch Circuit Fault, Front Driver's Side

Pinpoint Test N: DTC B2691 - Seat Belt Buckle Switch Circuit Fault, Front Driver's Side

WARNING: This page is about a different car, the 2008 Mercury Mariner and 2008 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: Always wear eye protection when servicing a vehicle. Failure to follow this instruction may result in serious personal injury.
WARNING: Do not handle, move or change the original horizontal mounting position of the restraints control module (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.
WARNING: Never probe the electrical connectors on air bag, safety canopy or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.
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 taking measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: The supplemental restraint system (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.
NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.
  1. N1 CHECK FOR CONTINUOUS AND ON-DEMAND DTCs 
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/ RCM/ Retrieve and Record On-Demand and Continuous Memory DTCs
    • Was on-demand DTC B2691 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  N2.
    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  N7.
  2. N2 CHECK CIRCUIT CR201 (BU/OG) FOR AN OPEN 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 C2041a and C2041b
    • Disconnect: Driver Safety Belt Buckle Switch C3065
    • Measure the resistance between RCM C2041b-25, circuit CR201 (BU/OG), harness side and driver safety belt buckle switch C3065-1, circuit CR201 (BU/OG), harness side.
      • Fig 1: Checking Circuit For Open
      GF0016844Courtesy of FORD MOTOR CO.
    • Is the resistance less than 0.5 ohm? 
    1. YES  : Go to  N3.
    2. NO  : REPAIR circuit CR201 (BU/OG). Go to  N8.
  3. N3 CHECK CIRCUIT GD183 (BK/WH) FOR AN OPEN 
    • Measure the resistance between driver safety belt buckle switch C3065-2, circuit GD183 (BK/WH), harness side and ground.
      • Fig 2: Measuring Resistance Between Connector And Ground
      G03946403Courtesy of FORD MOTOR CO.
    • Is the resistance less than 0.5 ohm? 
    1. YES  : Go to  N4.
    2. NO  : REPAIR circuit GD183 (BK/WH). Go to  N8.
  4. N4 CHECK CIRCUIT CR201 (BU/OG) FOR A SHORT TO VOLTAGE 
    • Disconnect: Driver Side Air Bag Module C367
    • Disconnect: Driver Safety Belt Buckle Pretensioner C3201
    • Repower the SRS. Do not  prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • Key in ON position.
    • Measure the voltage between driver safety belt buckle switch C3065-1, circuit CR201 (BU/OG), harness side and ground.
      • Fig 3: Measuring Voltage Between connector And Ground
      G04011523Courtesy of FORD MOTOR CO.
    • Is the voltage less than 0.2 volt? 
    1. YES  : Go to  N5.
    2. NO  : REPAIR circuit CR201 (BU/OG). Go to  N8.
  5. N5 CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH 
    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 .
    • Connect: RCM C2041a and C2041b
    • Connect a fused jumper wire between driver safety belt buckle switch C3065-1, circuit CR201 (BU/OG), harness side and C3065-2, circuit GD183 (BK/WH), harness side.
    • 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/ RCM/ Retrieve and Record On-Demand and Continuous Memory DTCs
    • DIAGNOSTIC TIP:  When viewing on-demand DTCs with the driver safety belt buckle switch circuits shorted together, a short to ground fault would normally be retrieved.
    • Did the driver safety belt buckle switch on-demand DTC change from indicating B2691 to B2434? 
    1. YES  : INSTALL a new driver safety belt buckle assembly. Refer to SAFETY BELT SYSTEM article. Go to  N8.
    2. NO  : Go to  N6.
  6. N6 CONFIRM THE RCM FAULT 
    NOTE: Make sure all restraint system components, 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.
    1. YES  : INSTALL a new RCM and CARRY OUT programmable module installation (PMI). REFER to Restraints Control Module (RCM) . Go to  N8.
    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 electrical connectors that were disconnected. 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 connector concerns found. Go to  N7.
  7. N7 CHECK FOR AN INTERMITTENT FAULT 
    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  N2.
    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 connector concerns found. Go to  N8.
  8. N8 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).
    • 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) Depowering and Repowering .
    • Key in ON position.
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/ Restraints/ Retrieve and Record On-Demand and Continuous Memory DTCs
    • Enter the following diagnostic mode on the diagnostic tool: Clear all RCM/OCSM Continuous Memory DTCs
    • Enter the following diagnostic mode on the diagnostic tool: Self Test/Restraints
    • Are any RCM or OCSM DTCs retrieved indicating a fault? 
    1. YES  : Do not clear any DTCs until all DTCs have been resolved. Go to the Supplemental Restraint System (SRS) DTC Chart in this article for pinpoint test direction.
    2. NO  : PROVE OUT the SRS. REPAIR is complete. RETURN the vehicle to the customer.
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