FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.
Home >> Ford Truck >> 2012 >> Explorer FWD L4-2.0L Turbo >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> B Code Charts >> BXXXX >> BXXXX:2B

BXXXX:2B




Diagnostic Routine V

Diagnostic Overview

BXXXX:2B (any BXXXX DTC with a 2B failure type) Signal Cross Coupled

Refer to Wiring Diagram Set 46 for schematic and connector information Electrical Diagrams.

The RCM (Restraints Control Module) monitors all deployable device and sensor circuits for a signal cross coupled (short) between circuits. If the RCM (Restraints Control Module) detects a short between the circuits of one device and another device, it stores a DTC (Diagnostic Trouble Code) for each of the signal cross coupled faults in memory. The RCM (Restraints Control Module) sends a message to the IPC (Instrument Panel Cluster) to illuminate the air bag warning indicator. When a normal loop fault is present (one loop is either shorted to battery/ground, open circuit or low resistance), then signal cross coupled diagnostics are not active. Once the normal loop fault is repaired, the signal cross coupled diagnostics resume.

DTC Fault Trigger Conditions










Visual Inspection and Diagnostic Pre-Checks

- Inspect the affected wiring harness(es) for damage, if accessible

Pinpoint Test

WARNING: Do not handle, move or change the original horizontal mounting position of the RCM (Restraints Control Module) while the RCM (Restraints Control Module) is connected and the ignition switch is ON. Failure to follow this instruction may result in the accidental deployment of the Safety Canopy(R) and cause serious personal injury or death.

WARNING: Never disassemble or tamper with seat belt deployable components, including pretensioners, load limiters and inflators. Never back probe deployable device electrical connectors. Tampering or back probing may cause an accidental deployment and result in personal injury or death.

WARNING: Never probe the electrical connectors on air bag, Safety Canopy(R) 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.

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:Only disconnect or reconnect SRS (Supplemental Restraint System) components when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS (Supplemental Restraint System).

NOTE: Always make sure the correct SRS (Supplemental Restraint System) component is being installed. Parts released for other vehicles may not be compatible even if they appear physically similar. Check the part number listed in the Ford Catalog Advantage or equivalent to make sure the correct component is being installed. If an incorrect SRS (Supplemental Restraint System) component is installed, DTCs (Diagnostic Trouble Codes) may set.

NOTE: The SRS (Supplemental Restraint System) must be fully operational and free of faults before releasing the vehicle to the customer.

1. RETRIEVE RCM (Restraints Control Module) DTCs (Diagnostic Trouble Codes)

1. Ignition ON.

2. Using a scan tool, perform RCM (Restraints Control Module) self-test to retrieve DTCs (Diagnostic Trouble Codes).

NOTE: Signal cross coupled DTCs (Diagnostic Trouble Codes) are retrieved only in pairs.

Were any signal cross coupled DTCs (Diagnostic Trouble Codes) retrieved on-demand during self-test?








2. CHECK THE AFFECTED DEPLOYABLE CIRCUITS FOR A SIGNAL CROSS COUPLED FAULT

1. Ignition OFF.

2. Depower the SRS (Supplemental Restraint System). REFER to Supplemental Restraint System (SRS) Depowering and Repowering - with Intelligent Access (IA) or REFER to Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) .

3. Disconnect RCM (Restraints Control Module) C310A and C310B.

4. Disconnect ALL of the affected SRS (Supplemental Restraint System) devices.

NOTE: Most signal cross coupled faults are due to connector and/or wiring harness damage. Carry out a thorough inspection of connector(s) and/or wiring harness for damage.

5. Using the following table, measure the resistance between the circuits of the affected SRS (Supplemental Restraint System) components.





Are the resistances greater than 10,000 ohms between the affected circuits?








3. CONFIRM THE RCM (Restraints Control Module) FAULT

NOTE: Make sure all SRS (Supplemental Restraint System) components and the RCM (Restraints Control Module) electrical connectors are connected before carrying out the self-test. If not, DTCs (Diagnostic Trouble Codes) will be recorded.

1. Prior to reconnecting any previously disconnected SRS (Supplemental Restraint System) component:

- inspect connector(s) (including any inline connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- inspect RCM (Restraints Control Module) C310A and C310B CPA (Connector Position Assurance) lever/lock for correct operation. REFER to Restraints Control Module (RCM) .
- repair any concerns found. Refer to Wiring Diagram Set 5 for schematic and connector information Electrical Diagrams.


2. Connect all previously disconnected restraint system component(s).

3. Connect RCM (Restraints Control Module) C310A and C310B.

4. Repower the SRS (Supplemental Restraint System). Do not prove out the SRS (Supplemental Restraint System) at this time. REFER to Supplemental Restraint System (SRS) Depowering and Repowering - with Intelligent Access (IA) or REFER to Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) .

5. Ignition ON.

6. Using a scan tool, perform RCM (Restraints Control Module) self-test to retrieve DTCs (Diagnostic Trouble Codes).

Were any signal cross coupled DTCs (Diagnostic Trouble Codes) retrieved on-demand during self-test?








4. CHECK FOR AN INTERMITTENT FAULT

NOTE: Most cross link faults are due to connector and/or wiring harness damage. Carry out a thorough inspection of connector(s) and/or wiring harness for damage.

1. Ignition OFF.

2. Depower the SRS (Supplemental Restraint System). REFER to Supplemental Restraint System (SRS) Depowering and Repowering - with Intelligent Access (IA) or REFER to Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) .

3. Disconnect ALL of the affected SRS (Supplemental Restraint System) devices. Refer to Wiring Diagram Set 46 for schematic and connector information Electrical Diagrams.

4. Inspect the wiring harness(es) for any type of damage. If damage is found, repair as necessary and Refer to Wiring Diagram Set 5 for schematic and connector information Electrical Diagrams.

5. Repower the SRS (Supplemental Restraint System). Do not prove out the SRS (Supplemental Restraint System) at this time. REFER to Supplemental Restraint System (SRS) Depowering and Repowering - with Intelligent Access (IA) or REFER to Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) .

6. Ignition ON.

7. Using a scan tool, perform RCM (Restraints Control Module) self-test to retrieve DTCs (Diagnostic Trouble Codes).

Were any signal cross coupled DTCs (Diagnostic Trouble Codes) retrieved on-demand during self-test?








5. CHECK FOR ADDITIONAL SRS (Supplemental Restraint System) DTCs (Diagnostic Trouble Codes)

1. Ignition OFF.

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.

2. Reconnect all SRS (Supplemental Restraint System) components (if previously disconnected).

3. If previously directed to depower the SRS (Supplemental Restraint System), repower the SRS (Supplemental Restraint System). Do not prove out the SRS (Supplemental Restraint System) at this time. REFER to Supplemental Restraint System (SRS) Depowering and Repowering - with Intelligent Access (IA) or REFER to Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) .

4. Ignition ON.

5. Using a scan tool, perform Restraints self-test to retrieve DTCs (Diagnostic Trouble Codes).

NOTE: When selecting Restraints from the Self Test menu, DTCs (Diagnostic Trouble Codes) are retrieved from the RCM (Restraints Control Module) and OCSM (Occupant Classification System Module).

Are any RCM (Restraints Control Module) and/or OCSM (Occupant Classification System Module) DTCs (Diagnostic Trouble Codes) retrieved on-demand during self-test?







pro multis Credits:Operation CHARM About Operation CHARM