LEMON Manuals: Even more car manuals for everyone
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 P: DTC B2792 - Cross Link Between Firing Loops >> Pinpoint Test P: DTC B2792 - Cross Link Between Firing Loops

Pinpoint Test P: DTC B2792 - Cross Link Between Firing Loops

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: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.
NOTE: The supplemental restraint system (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.
  1. P1 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
    • Enter the following diagnostic mode on the diagnostic tool: DataLogger/ RCM/ View and Record All B2792 Fault PIDs
      • Refer to PID list in Normal Operation to view B2792 fault PIDs.
    • Do any RCM on-demand B2792 fault PIDs indicate a fault? 
    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  P2.
    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  P4.
  2. P2 CHECK DEPLOYABLE CIRCUITS FOR A CROSS LINK FAULT 
    • Key in OFF position.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • Disconnect: RCM C2041a and C2041b
    • Disconnect ALL of the affected  deployable devices.
    • Using the following table, measure the resistance between the circuits of the affected deployable devices.
      DEPLOYABLE DEVICES

      Loop Connector - Pin Circuit
      Driver air bag module loop 1
      • Driver air bag module loop 1 electrical connector
      • RR101 (YE/GN)
       
      • Driver air bag module loop 1 electrical connector
      • CR101 (VT/BN)
      Driver air bag module loop 2
      • Driver air bag module loop 2 electrical connector
      • RR102 (WH)
       
      • Driver air bag module loop 2 electrical connector
      • CR102 (BU)
      Passenger air bag module loop 1
      • C256a-1
      • C256a-2
      • RR103 (VT/GN)
      • CR103 (GY/BU)
      Passenger air bag module loop 2
      • C256b-1
      • C256b-2
      • RR104 (WH/BU)
      • CR104 (YE/GY)
      Driver side air bag module
      • C367-1
      • C367-2
      • CR105 (GN/BN)
      • RR105 (GY/YE)
      Passenger side air bag module
      • C337-1
      • C337-2
      • CR106 (VT/GY)
      • RR106 (YE/OG)
      Driver safety canopy module
      • C9006-1
      • C9006-3
      • CR109 (BN/BU)
      • RR109 (BU/GN)
      Passenger safety canopy module
      • C9007-1
      • C9007-3
      • CR111 (BN/WH)
      • RR111 (YE/VT)
      Driver safety belt buckle pretensioner
      • C3201-1
      • C3201-2
      • CR120 (BU/OG)
      • RR120 (BN/GN)
      Passenger safety belt buckle pretensioner
      • C3202-1
      • C3202-2
      • CR122 (WH/OG)
      • RR122 (BN)
      Driver retractor pretensioner
      • C323-1
      • C323-2
      • RR146 (BU/BN)
      • CR146 (GY/VT)
      Passenger retractor pretensioner
      • C303-1
      • C303-2
      • RR147 (YE/VT)
      • CR147 (GN/OG)
    • Are the resistances greater than 10,000 ohms between the affected circuits? 
    1. YES  : Go to  P3.
    2. NO  : REPAIR the affected circuits. Go to  P5.
  3. P3 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.
    • Connect: All Previously Disconnected Restraint System Component(s)
    • Connect: RCM C2041a and C2041b
    • 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
    • Enter the following diagnostic mode on the diagnostic tool: DataLogger/ RCM /View and Record All DTC B2792 Fault PIDs
    • Was on-demand DTC B2792 retrieved? 
    1. YES  : INSTALL a new RCM and CARRY OUT programmable module installation (PMI). REFER to Restraints Control Module (RCM) . Go to  P5.
    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  P4.
  4. P4 CHECK FOR AN INTERMITTENT FAULT 
    • Key in OFF position.
    • Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering .
    • If a cross link fault for driver air bag loop 1 or loop 2 is present continuous, remove the driver air bag module. Refer to Driver Air Bag Module .
    • If a cross link fault for passenger air bag module loop 1 or loop 2 is present continuous, disconnect the passenger air bag module C256a and C256b.
    • If a cross link fault for driver side air bag is present continuous, disconnect the driver side air bag module C367.
    • If a cross link fault for passenger side air bag is present continuous, disconnect the passenger side air bag module C337.
    • If a cross link fault for driver safety canopy module is present continuous, disconnect the driver safety canopy module C9006.
    • If a cross link fault for passenger safety canopy module is present continuous, disconnect the passenger safety canopy module C9007.
    • If a cross link fault for driver safety belt buckle pretensioner is present continuous, disconnect the driver safety belt buckle pretensioner C3201.
    • If a cross link fault for passenger safety belt buckle pretensioner is present continuous, disconnect the passenger safety belt buckle pretensioner C3202.
    • If a cross link fault for driver retractor pretensioner is present continuous, disconnect the driver safety belt buckle pretensioner C323.
    • If a cross link fault for passenger retractor pretensioner is present continuous, disconnect the passenger safety belt buckle pretensioner C303.
    • 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
    • Enter the following diagnostic mode on the diagnostic tool: DataLogger/ RCM/ View and Record All B2792 Fault PIDs
      • Refer to PID list in Normal Operation to view B2792 fault PIDs.
    • Do any RCM on-demand B2792 fault PIDs indicate a 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  P2.
    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  P5.
  5. P5 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.
scientia non olet · About LEMON Manuals