Pinpoint Test R: DTC B2436 - Passenger Safety Belt Buckle Switch Circuit Open

WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. 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 a thorough Inspection and Verification before proceeding with the Pinpoint Test.

R1 CHECK FOR ON-DEMAND AND CONTINUOUS 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.

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: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: Retrieve/Record Continuous DTCs.
- Was DTC B2436 retrieved during the on-demand self test?
Yes : This is a hard fault. The fault condition is now present. This fault cannot be cleared until it is corrected and DTC is no longer retrieved during the on-demand self test. GO to R2

No : This is an intermittent fault. The fault condition is not present at this time. GO to R6.
R2 CHECK CIRCUIT 1514 (RD/BK) FOR AN OPEN
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Disconnect: RCM C310a and C310b.
- Disconnect: Passenger Safety Belt Buckle Switch and Belt Tension Sensor C3066.
- Measure the resistance between RCM C310b-26, circuit 1514 (RD/BK), harness side and passenger safety belt buckle switch and belt tension sensor C3066-1, circuit 1514 (RD/BK) harness side.
  
  Fig 1: Measuring Resistance Between RCM C310B Pin 26, Circuit 1514 And Passenger Safety Belt Buckle Switch And Belt Tension Sensor C3066 Pin 1, Circuit 1514
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohms?
Yes : GO to R3.

No : REPAIR circuit 1514 (RD/BK). GO to R7.
R3 CHECK CIRCUIT 1558 (TN/BK) FOR AN OPEN
- Measure the resistance between RCM C310b-24, circuit 1558 (TN/BK), harness side and passenger safety belt buckle switch and belt tension sensor C3066-2, circuit 1558 (TN/BK), harness side.
  
  Fig 2: Measuring Resistance Between RCM C310B Pin 24, Circuit 1558 And Passenger Safety Belt Buckle Switch And Belt Tension Sensor C3066 Pin 2, Circuit 1558
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
Yes : GO to R4.

No : REPAIR open in circuit 1558 (TN/BK). GO to R7.
R4 CHECK THE PASSENGER SAFETY BELT BUCKLE SWITCH
- Install a known good passenger safety belt buckle. Refer to SAFETY BELT SYSTEM .
- Connect: RCM C310a and C310b.
- 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 B2436 retrieved during the on-demand self test?
Yes : GO to R5.

No : Fault corrected. GO to R7.
R5 CONFIRM 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.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Reinstall the original passenger safety belt buckle.
- 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 B2436 retrieved during the on-demand self test?
Yes : INSTALL a new RCM . REFER to RESTRAINTS CONTROL MODULE (RCM) . GO to R7.

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. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to R7.
R6 CHECK FOR AN INTERMITTENT FAULT
- Key in OFF position.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Was DTC B2436 retrieved during the on-demand self test?
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 R2.

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. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to R7.
R7 CHECK FOR ADDITIONAL DTCs
- Refer to the continuous DTCs recorded during Step R1.
- Were any continuous DTCs retrieved during Step R1 ?
Yes : Do not clear any DTCs until all DTCs have been resolved. GO to the RESTRAINTS CONTROL MODULE (RCM) DIAGNOSTIC TROUBLE CODE (DTC) PRIORITY TABLE in this article for pinpoint test direction.

No : RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION . REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING . PROVE OUT the system. CLEAR all DTCs.