Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)

AIR BAG AND SAFETY BELT PRETENSIONER SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Components (Illustration 1 Of 2) (Part 1):

Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Components (Illustration 1 Of 2) (Part 2):

Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Components (Illustration 2 Of 2) (Part 1):

Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Components (Illustration 2 Of 2) (Part 2):

The air bag supplemental restraint system (SRS) is designed to provide increased collision protection for front seat and second row outboard occupants in addition to that provided by the 3-point safety belt system. The SRS will also provide increased collision protection for the rear occupants when equipped with optional safety canopy modules. Safety belt use is necessary to obtain the best occupant protection and to receive the full advantage of the SRS.

This vehicle line contains dual stage deployment (advanced restraint system) driver and front passenger air bag modules, except for the Escape Hybrid, which has a single stage front passenger air bag module. These vehicles can also be equipped with optional safety canopies that deploy from the A-pillar to the C-pillar upon a side impact or if a rollover condition is detected. Escape Hybrid, Mariner and late build Escape vehicles equipped with safety canopy modules are also equipped with seat side air bag modules. A unique restraints control module (RCM) is used on these vehicles which will detect a potential rollover condition. In addition, a front impact severity sensor is mounted to the radiator support bracket, a seat position sensor is mounted to the driver seat and a usage detection switch is added to the front driver and passenger outboard buckles.

Safety canopy modules deploy from the headliner, protecting the first and second row outboard occupants during a side impact or if a rollover condition is detected. Seat side air bag modules deploy from the outboard front seat backrest upon a side impact.

Before servicing the SRS, the system must be depowered.

Clockspring
The clockspring:
- is mounted on the steering column, behind the steering wheel.
- continuously transfers electrical signals from the restraints control module (RCM) to the driver air bag module.

Driver Air Bag Module

NOTE:
- The driver air bag (soft pack) and steering wheel can be serviced separately or as an assembly.
- In the event of an air bag deployment, the air bag (soft pack) and steering wheel must be serviced as an assembly.

The driver air bag module:
- is installed new as an assembly.
- is mounted in the center of the steering wheel.
- will deploy upon receiving a flow of current from the restraints control module (RCM).

Driver Seat Side Air Bag Module

NOTE:
- References to seat side air bag modules refer to the seat-mounted and not to the steering wheel or instrument panel mounted air bag components of the SRS.
- For additional information, when servicing a seat equipped with a seat side air bag module, refer to Seats.

A seat side air bag module provides protection of the thorax area (between the neck and abdomen) of the body, working in conjunction with the head protection provided by a safety canopy module. Only Escape Hybrid, Mariner and late build Escape vehicles equipped with safety canopy modules are equipped with seat side air bag modules.

The driver seat side air bag module:
- will deploy upon receiving a flow of current from the RCM initiated by the driver seat side impact sensor and internal RCM circuitry.
- is installed as an assembly.
- is mounted in the driver seat back.
- is used in conjunction with a safety canopy module on Escape Hybrid, Mariner and late build Escape vehicles only (seat side air bag modules are not equipped on early build Escape vehicles).

Driver Seat Side Air Bag Bridge Resistor

NOTE: Do not deactivate the seat side air bag circuit by removing the bridge resistor from the electrical connector.

If the seat side air bag bridge resistor is removed, an open circuit fault will be generated by the restraints control module (RCM).

If a restraint system diagnostic tool is installed at the seat side air bag electrical connector, a low-resistance fault will be generated.

The driver seat side air bag bridge resistor:
- is located beneath the driver seat.
- is equipped only on Escape Hybrid, Mariner and late build Escape vehicles that are not equipped with seat side air bag modules.

Electrical System
The electrical system that supports the air bag SRS:
- is powered from the battery through the ignition circuit.
- provides the electrical path from the restraints control module (RCM) to the SRS components.
- provides the electrical path from the RCM to the air bag indicator.
- provides the electrical path from the RCM to the data link connector (DLC).
- provides the electrical path from the RCM to the instrument cluster module.

Occupant Classification Sensor

CAUTION:
- It is necessary to rezero the OCS system when a front passenger seat cushion is disassembled, a new trim cover installed, or an OCS service kit is installed. A diagnostic tool is used to trigger the active command to carry out rezeroing of the OCS system.
- There are 2 occupant classification sensor (OCS) system service kits available for this vehicle (base seat and heated seat). Always make sure the correct OCS service kit is installed.
- Make sure the seat is completely assembled before rezeroing.
- The following precautions must be taken before rezeroing of the OCS system.
- Make sure the OCS system components are connected and no faults are present.
- Make sure the OCS system is not at a temperature below 0°C (32°F) or above 45°C (113°F) when initiating the rezeroing process. If the vehicle has been exposed to extreme cold or hot temperatures, the vehicle must be exposed and kept at a temperature within the limits, 0°C to 45°C (32°F to 113°F) for a minimum of 30 minutes.
- Make sure nothing is present on the passenger seat before rezeroing and nothing is placed on the seat during the rezeroing process.
- Make sure a minimum 5-second time period has passed after cycling the ignition switch ON before the rezeroing process.

NOTE:
- For best results in rezeroing, the OCS system should be at or near room temperature, 10°C to 29°C (50°F to 85°F).
- When using an NGS+ (NGS with Vehicle Communication Module (VCM) and the latest software update) to rezero the OCS system:
- select "FUNCTION TEST"
- select "SYSTEM RESET"
- view the on-screen information, then press "TRIGGER"

The NGS+ screen will then display "OCS RESET: REZERO." Press "DONE" (button 8) to rezero the OCS system. The NGS+ will display "TEST/FUNCTION SUCCESSFUL" once rezeroing of the OCS system is complete.

- To rezero the OCS system using the Worldwide Diagnostic System (WDS):
- select the "Toolbox" icon
- select "Body" from the menu
- select "Restraints" from the menu
- select "Seat Weight Sensor ReZero"

After selecting "Seat Weight Sensor ReZero", follow the on-screen prompts to carry out rezeroing of the OCS system.

- To identify between a production OCS system and a OCS system service kit, inspect the OCS ECU electrical connector.

A production OCS system allows the disconnect of the electrical connector from the OCS ECU.

An OCS system service kit (OCS service kit) has the OCS ECU electrical connector glued to the ECU, it cannot and should not be disconnected or altered. An OCS system service kit also has an in-line 10-pin connector between the OCS ECU and the seat wiring harness.

- The heated seat element on the front passenger seat cushion is not serviceable separately. If a new heated seat element is needed on the front passenger seat cushion, a new occupant classification sensor (OCS) service kit equipped with a heated seat element must be installed.
- If the first attempt to rezero the OCS system is unsuccessful, a second attempt must be made.

The seat occupant classification sensor system is found only on the front passenger seat. The front passenger seat occupant classification sensor (OCS) system is comprised of a silicone gel-filled bladder mounted in the seat cushion, a pressure sensor that is mounted to the seat frame and an electronic control unit which is also mounted to the seat frame. Pressure is applied to the OCS bladder when the weight of any occupant or object in the front passenger seat is present. The pressure is then transferred through a tube, is sensed by the OCS pressure sensor, then electronically communicated to the OCS electronic control unit. Based on programmed limits, the OCS electronic control unit will inform the restraints control module (RCM), via a High Speed Controller Area Network (CAN), of the necessary information. The RCM uses this information in determining if the passenger air bag module or passenger seat side air bag module is to be deployed in the event of a deployable collision. The OCS system components (seat cushion foam pad, bladder with pressure sensor and electronic control unit) are calibrated to each other and are serviced as an assembly. OCS system components are not to be installed separately. If installing a new OCS system, OCS system component or seat cushion foam pad, a new OCS system service kit (seat cushion foam pad, bladder with pressure sensor and electronic control unit) must be installed as an assembly.

The OCS system is also used for operation of the passenger Belt Minder. To deactivate or reactivate the passenger Belt Minder feature, refer to Instrument Panel, Gauges and Warning Indicators or the owner literature.

Passenger Air Bag Deactivation (PAD) Indicator
The passenger air bag deactivation (PAD) indicator is a visual indicator used to inform the front seat occupants of the passenger air bag deactivation state. The PAD indicator is a stand-alone lamp installed into the vehicle instrument panel in a position visible to each front seat occupant.

The restraints control module (RCM) controls the state of the PAD indicator through a direct hardwire connection, based on information provided by the occupant classification sensor (OCS) system. The PAD indicator is lit to indicate the passenger air bag module is disabled. An exemption to this is when the front passenger seat is determined to be empty, and therefore indication of a deactivated passenger air bag module is not necessary. In all other cases, the PAD indicator is unlit when the passenger air bag module is enabled.

When the ignition switch is in the ON position, the PAD indicator prove-out period is initiated by the RCM. The RCM briefly activates the PAD indicator to prove-out the indicator function and verify to the front occupants correct functional operation of the PAD indicator.

The PAD indicator will lit/unlit within 1.0 to 1.5 seconds of a change of state from the OCS system.

When an OCS system fault is present the SRS defaults the passenger air bag module to enabled regardless of the size of the occupant in the front outboard passenger seat. The PAD indicator will be unlit.

Passenger Air Bag PAD Indicator Status:

The table indicates the passenger air bag status and the PAD indicator status based the size of the front outboard passenger occupant.

Passenger Air Bag Module
The passenger air bag module:
- is installed new as an assembly.
- is mounted in the passenger side of the instrument panel.
- will deploy upon receiving a flow of current from the restraints control module (RCM).
- is single stage unit on Escape Hybrid vehicles.
- is a dual stage unit on Escape and Mariner vehicles.

Passenger Seat Side Air Bag Module

NOTE:
- References to seat side air bag modules refer to the seat-mounted and not to the steering wheel or instrument panel mounted air bag components of the SRS.
- For additional information, when servicing seat equipped with a seat side air bag module, refer to Seats.

A seat side air bag module provides protection of the thorax area (between the neck and abdomen) of the body, working in conjunction with the head protection provided by a safety canopy module. Only Escape Hybrid, Mariner and late build Escape vehicles equipped with safety canopy modules are equipped with seat side air bag modules.

The passenger seat side air bag module:
- will deploy upon receiving a flow of current from the RCM initiated by the passenger seat side impact sensor and internal RCM circuitry.
- is installed as an assembly.
- is mounted in the passenger seat back.
- is used in conjunction with a safety canopy module on Escape Hybrid, Mariner and late build Escape vehicles only (seat side air bag modules are not equipped on early build Escape vehicles).

Passenger Seat Side Air Bag Bridge Resistor

NOTE: Do not deactivate the seat side air bag circuit by removing the bridge resistor from the electrical connector.

If the seat side air bag bridge resistor is removed, an open circuit fault will be generated by the restraints control module (RCM).

If a restraint system diagnostic tool is installed at the seat side air bag electrical connector, a low-resistance fault will be generated.

The passenger seat side air bag bridge resistor:
- is located beneath the passenger seat.
- is equipped only on Escape Hybrid, Mariner and late build Escape vehicles that are not equipped with seat side air bag modules.

Restraints Control Module (RCM)

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 these instructions may result in the inadvertent deployment of the safety canopy and risk of personal injury.
- The RCM orientation is critical for correct system operation. If a vehicle equipped with an air bag supplemental restraint system (SRS) has been involved in a collision in which the center tunnel area has been damaged, inspect the mounting and bracket for deformation. If damaged, a new RCM must be installed whether or not the air bags have deployed. In addition, make sure the area of the RCM mounting is restored to its original condition.

NOTE: When installing a new restraints control module (RCM), always make sure the correct RCM is being installed. If an incorrect RCM is installed, erroneous DTCs will result.

The restraints control module carries out the following functions:
- deploys the air bag(s) in the event of a deployable crash.
- activates the safety belt buckle pretensioners to remove slack from the safety belt.
- monitors the SRS for faults.
- illuminates the air bag indicator if a fault is detected.
- flashes the air bag indicator to indicate the lamp fault code (LFC) detected.
- communicates through the data link connector (DLC) the current or historical diagnostic trouble codes (DTCs).
- signals the instrument cluster module to activate a chime if the air bag indicator is not available and another SRS fault exists.

The RCM monitors the SRS for possible faults. If a fault is detected while the ignition switch is in the ON position, the RCM will illuminate the air bag indicator located in the instrument cluster.

When the ignition is cycled (turned off and then on), the air bag indicator will prove out by lighting for 6 seconds and then off for 2 seconds. After the prove out, the air bag indicator will then flash the 2-digit LFC if a SRS fault exists. The air bag indicator will flash the LFC 5 times, then it will remain illuminated for the rest of the key cycle. The RCM will also communicate the current and historical DTCs through the DLC, to the diagnostic tool. If the air bag indicator does not function, and the system detects a fault condition, the RCM will signal the instrument cluster module to activate an audible chime. The chime is a series of 5 sets of 5 tone bursts. If the chime is heard, the SRS and the air bag indicator require repair.

LFCs are prioritized. If 2 or more faults occur at the same time, the fault having the highest priority will be displayed. After that fault has been corrected, the next highest priority fault will be displayed.

The RCM includes a backup power supply. This feature provides 150 ms of backup power to deploy the front air bags and pretensioners in the event that the ignition circuit is lost or damaged during impact.

The backup power supply will deplete its stored energy approximately 1 minute after the battery ground cable is disconnected.

Safety Belt Buckle Switches
As part of the supplemental restraint system (SRS), the front safety belt buckles are equipped with safety belt buckle switches. The safety belt buckle switches are comprised of integrated circuits called Hall-effect sensors. The safety belt buckle switches (Hall-effect sensors) are located in the driver and passenger safety belt buckles. The safety belt buckle switches indicate to the restraints control module (RCM) whether the safety belts are connected or disconnected. The RCM uses this information in determining the deployment rate of the dual-stage driver and passenger air bag modules. The RCM also communicates the driver safety belt buckle switch status to the instrument cluster module, which monitors the information to control the safety belt warning indicator.

Safety Belt Buckle Pretensioners - All Vehicles
As part of the SRS, the safety belt buckles are equipped with pretensioners. The safety belt buckle pretensioners remove excess slack from the safety belt webbing. The pretensioners are activated by the restraints control module (RCM) when the module detects a impact event force exceeding a programmed limit.

Safety Belt Retractor Pretensioner - Escape Hybrid Only
As part of the SRS, the driver safety belt retractor for the Escape Hybrid is equipped with a pretensioner. The pretensioner removes excess slack from the safety belt webbing. The pretensioner is activated by the RCM when the module detects an impact event force exceeding a programmed limit.

Safety Belt Tension Sensor
The safety belt tension sensor:
- is part of the front outboard passenger safety belt and retractor assembly.
- is located at the safety belt anchor point.
- is used in conjunction with the occupant classification sensor (OCS) system.
- is a 3-wire Hall-effect sensor that is part of the front passenger safety belt and retractor assembly.

The safety belt tension sensor is used by the OCS system to identify the presence of a child safety seat on the front outboard passenger seat, when the child safety seat is installed according to manufacturer instructions. The safety belt tension sensor senses the tension on the safety belt assembly then provides an output to the OCS system electronic control unit (ECU), indicating that the safety belt assembly is cinched. After sensing the weight applied to the seat by the occupant and using the safety belt tension sensor input, the OCS system determines how the occupant should be classified and communicates this information to the restraints control module (RCM). If the occupant is classified to be a child, the RCM will then automatically deactivate the passenger air bag module.

Safety Canopy Bridge Resistor

CAUTION: Do not deactivate the safety canopy module circuit or seat side air bag module circuit by removing the bridge resistor from the electrical connector.

If the safety canopy or seat side air bag bridge resistor is removed, an open circuit fault will be generated by the restraints control module (RCM).

If a restraint system diagnostic tool is installed at the safety canopy or seat side air bag electrical connector, a low-resistance fault will be generated.

NOTE: If the headliner near each B-pillar has the word "AIRBAG" embossed on it, the vehicle is equipped with safety canopy modules.

The safety canopy bridge resistor:
- is equipped on vehicles without safety canopy modules.
- must not be removed during deactivation.
- is attached to the headliner near the LH D-pillar.

Safety Canopy Module

Vehicles With Moon Roof:

Vehicles Without Moon Roof:

WARNING: Anytime the safety canopy has deployed, the headliner, and all A-, B- and C- upper trim panels and attaching hardware must be replaced along with any other damaged components and hardware. Failure to do so can result in personal injury in the event of a safety canopy deployment.

NOTE:
- If the headliner near each B-pillar has the word "AIRBAG" embossed on it, the vehicle is equipped with safety canopy modules.

The side air curtain module or safety canopy:
- is installed as an assembly.
- is mounted above the headliner.
- attaches from the A-pillar frame to the C-pillar frame.

- There are 2 different safety canopy modules, 1 for vehicles equipped with a moon roof and 1 for vehicles without a moon roof. The safety canopy modules are NOT interchangeable. If installing a new safety canopy module, the correct safety canopy module MUST be installed for the vehicle application.

Seat Track Position Sensor
The seat track position sensor is a Hall-effect sensor located on the driver seat track. The seat track position sensor informs the restraints control module (RCM) of the driver seat position. Based on programmed limits, the seat track position sensor will inform the RCM of the driver seat position. The RCM uses this information in determining the deployment rate of the dual-stage driver air bag module.

Sensors

WARNING:
- The restraints control module (RCM) orientation is critical for correct system operation. If a vehicle equipped with an air bag supplemental restraint system (SRS) has been involved in a collision in which the center tunnel area has been damaged, inspect the mounting and bracket for deformation. If damaged, a new RCM must be installed whether or not the air bags have deployed. In addition, make sure the area of the RCM mounting is restored to its original condition.
- Vehicle sensor orientation is critical for correct system operation. If a vehicle equipped with an air bag supplemental restraint system (SRS) is involved in a collision, inspect the sensor mounting bracket and wiring pigtail for deformation. Replace and correctly position the sensor or any other damaged supplemental restraint system (SRS) components whether or not the air bag is deployed.

For these vehicles, the SRS uses up to 5 satellite sensors in addition to the RCM. The RCM is mounted to the center tunnel beneath the console. All vehicles will have a front impact severity sensor and it is located in the front-center of the vehicle, mounted on the radiator support bracket. If the vehicle is equipped with safety canopies, there are 4 additional side impact sensors. The 4 additional sensors are located at the base of each B-pillar and mounted on the C-pillar. The LH and RH C-pillar mounted side impact sensors are interchangeable. Mounting orientation is critical for correct operation of all impact and rollover sensors.