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Diagnostic Routine E




Diagnostic Routine E

Diagnostic Overview

B0020:11, B0020:12, B0020:13 and B0020:1A

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

Normal Operation and Fault Conditions

The RCM (Restraints Control Module) continuously monitors the driver seat side air bag module circuits for the following faults:

- Resistance out of range

- Unexpected voltage

- Short to ground

- Faulted driver seat side air bag module

If a fault is detected, the RCM (Restraints Control Module) stores DTC (Diagnostic Trouble Code) B0020:11, B0020:12, B0020:13 or B0020:1A in memory and sends a message to the IPC (Instrument Panel Cluster) to illuminate the air bag warning indicator.

The RCM (Restraints Control Module) analyzes the deployment loop resistance to determine if a fault exists. The value displayed in the PID (Parameter Identification) is the deployment loop resistance measured by the RCM (Restraints Control Module). If the value displayed is lower or higher than the desired range (refer to diagram below), the RCM (Restraints Control Module) can set a DTC (Diagnostic Trouble Code). As the deployment loop resistance drifts farther outside the desired range, the chance for a DTC (Diagnostic Trouble Code) increases. Small variations in resistance can occur due to the effect of road vibrations on terminal fit. Crimps and terminals can be affected by stress and harness movement and can cause an increase in resistance due to wire strain. These variables can result in an intermittent fault. For this reason, the test requires the PID (Parameter Identification) value to be within the desired range before the fault is considered repaired, regardless if the module is reporting an on-demand DTC (Diagnostic Trouble Code) at the time of diagnosis. Following this direction helps make sure that minor changes in resistance do not create a repeat concern. This test uses process of elimination to diagnose each part of the deployment loop circuit including:

- Wiring

- Connections

- Driver seat side air bag module

- RCM (Restraints Control Module)





DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Inspect for damaged wiring harness(es)

- Inspect for loose or damaged connectors

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 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.

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.

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(TM) 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).

Was DTC (Diagnostic Trouble Code) B0020:11, B0020:12, B0020:13 or B0020:1A retrieved on-demand during self-test?






2. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL RESISTANCE (DEPLOY_10_R) PID (Parameter Identification)

1. Using a scan tool, view RCM (Restraints Control Module) PIDs (Parameter Identifications).

2. Monitor and record the resistance value displayed by the DEPLOY_10_R PID (Parameter Identification).

Does the PID (Parameter Identification) value read between 1.7 and 2.78 ohms?






3. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL RESISTANCE (DEPLOY_10_R) PID (Parameter Identification) WHILE CARRYING OUT THE HARNESS TEST

1. While monitoring the DEPLOY_10_R PID (Parameter Identification), carry out the harness test of the driver seat side air bag module circuits and accessible connectors (including any inline connectors) by wiggling and flexing the wire harness and connectors frequently. Record the resistance value indicated by the PID (Parameter Identification).

Does the PID (Parameter Identification) value read between 1.7 and 2.78 ohms while carrying out the harness test?






4. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL DTC (Diagnostic Trouble Code) FOR A FAULT STATUS CHANGE (LOW RESISTANCE INDICATED)

NOTE: This pinpoint test step attempts to change the fault reported by the RCM (Restraints Control Module) by inducing a different fault condition. If the reported fault changes, this indicates the RCM (Restraints Control Module) is functioning correctly and is not the source of the 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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

3. Disconnect Driver Seat Side Air Bag Module (Inline) C300B.

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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

5. Ignition ON.

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

7. DIAGNOSTIC TIP: When viewing DTCs (Diagnostic Trouble Codes) with the driver seat side air bag module disconnected, an open circuit fault is normally retrieved. Due to the inline seat connector being disconnected, DTCs (Diagnostic Trouble Codes) will also set for the seat track position sensor and safety belt buckle switch.

Did the on-demand DTC (Diagnostic Trouble Code) change from B0020:1A to B0020:13?






5. CHECK FOR A SHORT BETWEEN DRIVER SEAT SIDE AIR BAG CIRCUITS

1. Ignition OFF.

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

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

4. Measure:





Is the resistance greater than 10,000 ohms?






6. CHECK THE DRIVER SEAT SIDE AIR BAG CIRCUITS FOR AN OPEN

1. Ignition OFF.

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

3. Disconnect Driver Seat Side Air Bag Module (Inline) C300B.

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

5. Measure:





Is the resistance less than 0.5 ohm?






7. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL DTC (Diagnostic Trouble Code) FOR A FAULT STATUS CHANGE (OPEN INDICATED)

NOTE: This pinpoint test step attempts to change the fault reported by the RCM (Restraints Control Module) by inducing a different fault condition. If the reported fault changes, this indicates the RCM (Restraints Control Module) is functioning correctly and is not the source of the fault.

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

2. Connect a fused jumper wire:





3. 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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

4. Ignition ON.

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

6. DIAGNOSTIC TIP: When viewing DTCs (Diagnostic Trouble Codes) with the driver seat side air bag module circuits shorted together, a low resistance fault is normally retrieved. Due to the inline seat connector being disconnected, DTCs (Diagnostic Trouble Codes) will also set for the seat track position sensor and safety belt buckle switch.

Did the on-demand DTC (Diagnostic Trouble Code) change from B0020:13 to B0020:1A?






8. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL DTC (Diagnostic Trouble Code) FOR A FAULT STATUS CHANGE (SHORT TO GROUND INDICATED)

NOTE: This pinpoint test step attempts to change the fault reported by the RCM (Restraints Control Module) by inducing a different fault condition. If the reported fault changes, this indicates the RCM (Restraints Control Module) is functioning correctly and is not the source of the 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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

3. Disconnect Driver Seat Side Air Bag Module (Inline) C300B.

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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

5. Ignition ON.

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

7. DIAGNOSTIC TIP: When viewing DTCs (Diagnostic Trouble Codes) with the driver seat side air bag module disconnected, an open circuit fault is normally retrieved. Due to the inline seat connector being disconnected, DTCs (Diagnostic Trouble Codes) will also set for the seat track position sensor and safety belt buckle switch.

Did the on-demand DTC (Diagnostic Trouble Code) change from B0020:11 to B0020:13?






9. CHECK THE DRIVER SEAT SIDE AIR BAG CIRCUITS FOR A SHORT TO GROUND

1. Ignition OFF.

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

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

4. Measure:





Are the resistances greater than 10,000 ohms?






10. CHECK THE DRIVER SEAT SIDE AIR BAG CIRCUITS FOR A SHORT TO VOLTAGE

1. Ignition OFF.

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

3. Disconnect Driver Seat Side Air Bag Module (Inline) C300B.

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

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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

6. Ignition ON.

7. Measure:





Is any voltage present?






11. CONFIRM THE DRIVER SEAT SIDE AIR BAG 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. Ignition OFF.

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

3. 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 damaged, 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). Service and Repair
- repair any concerns found. Refer to Wiring Diagram Set 5 for schematic and connector information Electrical Diagrams.

4. Connect Driver Seat Side Air Bag Module (Inline) C300B.
- Tighten to 1 Nm (9 lb-in).

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

6. 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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

7. Ignition ON.

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

Was the original DTC (Diagnostic Trouble Code) retrieved on-demand during self-test?






12. 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. Ignition OFF.

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

3. 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 damaged, 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). Service and Repair
- repair any concerns found. Refer to Wiring Diagram Set 5 for schematic and connector information Electrical Diagrams.

4. Connect Driver Seat Side Air Bag Module (Inline) C300B (if previously disconnected).
- Tighten to 1 Nm (9 lb-in).

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

6. 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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

7. Ignition ON.

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

Was the original DTC (Diagnostic Trouble Code) retrieved on-demand during self-test?






13. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL RESISTANCE (DEPLOY_10_R) PID (Parameter Identification) FOR AN INTERMITTENT LOW RESISTANCE OR OPEN CIRCUIT FAULT

1. Using a scan tool, view RCM (Restraints Control Module) PIDs (Parameter Identifications).

2. While monitoring the DEPLOY_10_R PID (Parameter Identification), attempt to recreate the fault by wiggling connectors (including any inline connectors) and flexing the wire harness frequently. Record the resistance value indicated by the PID (Parameter Identification).

Does the PID (Parameter Identification) value read between 1.7 and 2.78 ohms?






14. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL CIRCUITS FOR AN INTERMITTENT SHORT TO GROUND FAULT

1. Attempt to recreate the fault by wiggling connectors (including any inline connectors) and flexing the wire harness frequently.

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

Was DTC (Diagnostic Trouble Code) B0020:11 retrieved on-demand during self-test?






15. CHECK THE LEFT SIDE AIRBAG DEPLOYMENT CONTROL CIRCUITS FOR AN INTERMITTENT SHORT TO BATTERY 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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

3. Disconnect Driver Seat Side Air Bag Module (Inline) C300B.

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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

5. Ignition ON.

6. Attempt to recreate the fault by wiggling connectors (including any inline connectors) and flexing the wire harness frequently.

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

Was DTC (Diagnostic Trouble Code) B0020:12 retrieved on-demand during self-test?






16. CHECK THE HARNESS AND CONNECTORS

1. Ignition OFF.

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

3. Disconnect Driver Seat Side Air Bag Module (Inline) C300B.

- Inspect connector(s) (including any inline connectors) for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
- Inspect wire harness for any damage, pinched, cut or pierced wires.

4. Inspect RCM (Restraints Control Module) C310A and C310B CPA (Connector Position Assurance) lever/lock for correct operation. REFER to Restraints Control Module (RCM). Service and Repair

Were any concerns found?






17. 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).
- For the driver seat inline connector C300B, tighten to 1 Nm (9 lb-in).

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 Supplemental Restraint System (SRS) Depowering and Repowering - without Intelligent Access (IA) . Service and Repair

4. Ignition ON.

5. Using a scan tool, perform theRestraints 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?





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