Pinpoint Test R: DTC B2438 - Passengers Seat Belt Buckle Switch Short To Ground
WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
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.
CAUTION:
Use the correct probe adapter(s) when making 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.
- R1 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 B2438 retrieved?
- 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 R2.
- 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 R5.
- R2 CHECK THE PASSENGER 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 .
- Disconnect: Passenger Safety Belt Buckle Switch C3066
- 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 passenger safety belt buckle switch disconnected, a open circuit fault would normally be retrieved.
- Did the passenger safety belt buckle switch on-demand DTC change from indicating B2438 to B2436?
- YES : INSTALL a new passenger safety belt buckle assembly. REFER to SAFETY BELT SYSTEM . Go to R6.
- NO : Go to R3.
- R3 CHECK CIRCUIT CR203 (GY/VT) FOR A SHORT TO GROUND BETWEEN THE RCM AND PASSENGER 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
- Measure the resistance between passenger seat belt buckle switch C3066-2, circuit CR203 (GY/VT), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Fig 1: Measuring Resistance Between Passenger Safety Belt Buckle Switch C3066-2, Circuit CR203 (GY/VT) & GroundCourtesy of FORD MOTOR CO.
- R4 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: Passenger Safety Belt Buckle Switch C3066
- 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 B2438 retrieved?
- YES : INSTALL a new RCM. REFER to Restraints Control Module (RCM) . Go to R6.
- 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 connector that were disconnected. Go to R5.
- R5 CHECK FOR AN INTERMITTENT FAULT
- Key in OFF position.
- Enter the following diagnostic mode on the diagnostic tool: Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs
- Was on-demand DTC B2438 retrieved?
- 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. REPAIR any intermittent concerns found. Go to R6.
- R6 CHECK FOR ADDITIONAL DTCs
- Refer to the continuous memory DTCs recorded during Step R1.
- Were any continuous memory DTCs retrieved during Step R1?
- YES : Do not clear any DTCs until all DTCs have been resolved. Go to the Supplemental Restraint System (SRS) Diagnostic Trouble Code (DTC) Chart for pinpoint test direction.
- NO : RECONNECT the SRS. If previously directed to depower the SRS, REPOWER the SRS REFER to Supplemental Restraint System (SRS) Depowering and Repowering . PROVE OUT the SRS. CLEAR all RCM DTCs.