2010 JAGUAR XFR srs

Published: 30-May-2012
Supplemental Restraint System - Air Bag and Safety Belt Pretensioner
Supplemental Restraint System (SRS) - Overview
Description and Operation

OVERVIEW


WARNING: All pyrotechnic devices are dangerous. Before performing any procedures on any pyrotechnic device, read all
information contained within the Standard Workshop Practices section of this manual.
Refer to: Standard Workshop Practices (100-00 General Information, Description and Operation).
The SRS (supplemental restraint system) provides additional protection for the vehicle occupants in certain impact conditions.
The system is controlled by the RCM (restraints control module), which is mounted beneath the floor console. The system
includes twin stage drivers and front passenger airbags.
The RCM receives inputs from various sensors around the vehicle and determines which, if any, airbags should be deployed.
The SRS features an occupant detection system. The occupant detection system comprises a mat fitted inside the front passenger seat. By monitoring the condition of the mat, the RCM can determine if the front passenger seat is occupied. It uses this information to determine which airbags to deploy in the event of an impact. This information is also used to illuminate the
safety belt instrument cluster warning lamp if the front passenger seat is occupied and the safety belt is not engaged.

North American Specification (NAS) vehicles also feature an occupant classification system. The occupant classification system
comprises a control module, pressure pad and safety belt tension sensor. The system can determine the size and weight of the
front seat passenger. This information is transmitted to the RCM over the high speed CAN (controller area network) bus. The RCM uses this information to help determine which airbags to deploy in the event of an impact.

Published: 26-Jun-2012
Supplemental Restraint System - Air Bag and Safety Belt Pretensioner
Supplemental Restraint System (SRS) - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired; D = High speed CAN (controller area network) bus



Item Description 1 Battery 2 BJB (battery junction box) 3 RJB (rear junction box) 4 Occupant classification system control module (NAS only) 5 Safety belt tension sensor (NAS only)

Driver Passenger Applicable Pretensioner Driver airbag Passenger airbag Fastened - -
Fired at pretensioner
threshold Fired at belt fastened
threshold - Unfastened - - Not fired
Fired at belt unfastened
threshold - - Fastened Occupied allow
Fired at pretensioner
threshold -
Fired at belt fastened
threshold - Fastened
Unoccupied inhibit/empty Fired at pretensioner
threshold - Not fired - Unfastened Occupied allow Not fired -
Fired at belt unfastened
threshold Unfastened
Unoccupied inhibit/empty Not fired - Not fired The battery disconnect unit is fired:

At driver and passenger airbag belt fastened threshold in a frontal impact
At the driver and passenger side impact threshold in a side impact
At the rear impact threshold in a rear impact.

Crash Signal

When the RCM outputs any of the fire signals it also outputs a crash signal to the RJB and the ECM (engine control module) on the high speed CAN. The crash signal is also hardwired to the ECM and the RJB. The instrument cluster picks up the crash signal from the high speed CAN and gateways it to the LCM (lighting control module). On receipt of the crash signal, the RJB goes into a crash mode and the ECM cuts the power supply to the fuel pump relay. In the crash mode, the RJB: Activates all of the unlock signals of the vehicle locking system, even if the vehicle is already unlocked.
Ignores all locking/superlocking inputs until it receives an unlock input, when it returns the locking system to normal
operation.
Activates the interior lamps. The interior lamps remain on permanently until they are manually switched off at the lamp
unit, or the RJB crash mode is switched off and they return to normal operation. Disables the rear window child lock input until the crash mode is switched off.
Sends a crash message to the LCM, to activate the hazard flashers. The hazard flashers remain on until cancelled by the hazard warning switch or the crash mode is switched off.
The RJB crash mode is switched off by a valid locking and unlocking cycle of the locking system.


Restraints Control Module Component Description



The RCM is installed on the top of the transmission tunnel, in line with the B pillars, and controls operation of the SRS (supplemental restraint system). The main functions of the RCM include:
Crash detection and recording
airbag and pre-tensioner firing
Self-test and system monitoring, with status indication via the airbag warning lamp and non-volatile storage of fault
information.
The RCM determines which elements of the SRS are to be deployed by using two internal areas:

and the safety belt buckle sensor. Based on this data, the RCM decides which level of airbag module deployment is required and forwards the information to the second area, the deployment handler.

The deployment handler evaluates the status of the seat track position sensor and safety belt buckle sensors before a decision
is made about which restraints should finally be deployed.

Data from the side crash sensors is used by the RCM in conjunction with acceleration data from the RCM internal accelerometer to make a deployment decision. The RCM processes the acceleration data and subject to an impact being of high enough severity, decides whether the side airbag module should be deployed.

On board testing of the airbag modules, front safety belt pretensioner firing circuits, warning indicator circuits and module
status (the crash and side impact sensors perform basic self-tests) is performed by the RCM together with the storing of fault codes.

The RCM drives the SRS indicator on the instrument pack via a CAN signal. If the warning lamp fails, a fault code is recorded and a warning tone is sounded in place of the lamp if a further fault occurs. It also provides a temporary back-up power supply
to operate the airbag modules in the event that in crash conditions, the battery supply is lost. In the event of a crash, it
records certain data which can be accessed via the diagnostic connector.

A safing sensor in the RCM provides confirmation of an impact to verify if airbag and pretensioner activation is necessary. A roll-over sensor monitors the lateral attitude of the vehicle. Various firing strategies are employed by the RCM to ensure that during an accident only the appropriate airbags and pretensioners are fired. The firing strategy used also depends on the
inputs from the safety belt switches and the occupant monitoring system.

An energy reserve in the RCM ensures there is always a minimum of 150 milliseconds of stored energy available if the power supply from the ignition switch is disrupted during a crash. The stored energy is sufficient to produce firing signals for the
driver airbag, the passenger airbag and the safety belt pretensioners.

When the ignition is switched on, the RCM performs a self-test and then performs cyclical monitoring of the system. If a fault is detected the RCM stores a related fault code and illuminates the airbag warning indicator. The faults can be retrieved by the recommended Jaguar diagnostic tool over the CAN bus. If a fault that could cause a false fire signal is detected, the RCM disables the respective firing circuit, and keeps it disabled during a crash event.

Clock Spring



The clockspring is installed on the steering column to provide the electrical interface between the fixed wiring harness of the
steering column and the components that rotate with the steering wheel, i.e. the driver airbag, the horn and the steering
wheel switch packs.

The clockspring consists of a plastic cassette which incorporates an outer cover fixed to the steering column and an inner rotor
which turns with the steering wheel. Four securing lugs attach the cover to the multifunction switch on the steering column.
The rotor is keyed to the steering wheel by a drive peg. A lug on the underside of the rotor operates the self-cancelling feature
of the turn signal indicator switch. A ribbon lead, threaded on rollers in the rotor, links two connectors on the cover to two
connectors on the rotor. Link leads for the driver airbag are installed in one of the connectors on the rotor.

To prevent damage to the ribbon lead, both the steering and the clockspring must be centralized when removing and installing
the clockspring or the steering wheel. The clockspring is centralized when the drive peg is at six o'clock and 50 - 100% of a
yellow wheel is visible in the viewing window.

Replacement clocksprings are fitted with a stopper, which locks the cover to the rotor, in the central position. The stopper must
be broken off when the replacement clockspring is installed.

Published: 10-Jul-2014
Supplemental Restraint System - Air Bag and Safety Belt Pretensioner
Supplemental Restraint System (SRS)
Diagnosis and Testing

Principle of Operation

For a detailed description of the supplemental restraints system and operation, refer to the relevant Description and Operation
section in the workshop manual. REFER to: (501-20B Supplemental Restraint System)

Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) (Description and Operation), Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) (Description and Operation), Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) (Description and Operation).
Inspection and Verification


WARNING: TO AVOID ACCIDENTAL DEPLOYMENT AND POSSIBLE PERSONAL INJURY, THE BACKUP POWER SUPPLY MUST
BE DEPLETED BEFORE REPAIRING OR REPLACING ANY AIR BAG SUPPLEMENTAL RESTRAINT SYSTEM (SRS) COMPONENTS. TO
DEPLETE THE BACKUP POWER SUPPLY ENERGY, DISCONNECT THE BATTERY GROUND CABLE AND WAIT ONE MINUTE. FAILURE
TO FOLLOW THIS INSTRUCTION MAY RESULT IN PERSONAL INJURY.


CAUTION: Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does not
guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle.


NOTE: Given the legal implications of a restraints system failure, harness repairs to Air Bag module circuits are not
acceptable. Where the text refers to "REPAIR the circuit", this will normally mean the replacement of a harness.
1. Verify the customer concern.

2. Visually inspect for obvious signs of damage and system integrity.



3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to
the next step.
4. If the cause is not visually evident, check for Diagnostic Trouble Codes (DTCs) and refer to the DTC Index.

DTC Index

For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this vehicle, please refer to Section 100-00.
REFER to: Diagnostic Trouble Code (DTC) Index - DTC: Restraints Control Module (RCM) (100-00 General Information, Description and Operation). Electrical

Battery condition, state of charge
Make sure all electrical connector(s) are engaged correctly on the air bag circuits
Wiring harness
Air bag module(s)
Make sure the restraints control module (RCM) is correctly installed
Fuse(s)
Sensor(s)
Pretensioner(s)
Warning lamp bulb(s) Visual Inspection
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Supplemental Restraint System - Air Bag Disposal
General Procedures

Deployed Air Bag Published: 11-May-2011

1. WARNING: Always wear safety glasses when repairing an air bag
supplemental restraint system (SRS) vehicle and when handling an air
bag module. Failure to follow this instruction may result in personal
injury.

Deployed air bag modules are to be disposed of as special waste and
must comply with local environmental requirements, if in doubt, contact
Authority for disposal requirements.


2. NOTE: The storage, transportation, disposal, and/or recycling of air
bag module components must be carried out in accordance with all
applicable federal, state and local regulations including, but not limited
to, those governing building and fire codes, environmental protection,
occupational health and safety, and transportation.

Modules removed and deployed by Jaguar service are to be returned to
the importer for disposal.

Undeployed Air Bag — Inoperative

1. WARNING: Carry a live air bag module with the air bag and trim
cover or deployment door pointed away from your body. This will reduce
the risk of injury in the event of an accidental deployment. Failure to
follow this instruction may result in personal injury.

NOTE: All inoperative air bag modules have been placed on the
Mandatory Return List. All discolored or damaged air bag modules must
be treated the same as any inoperative live air bag being returned.
Failure to follow this instruction may result in personal injury.

Remove the inoperative driver air bag module or passenger air bag
module. For additional information Driver Air Bag Module or Passenger Air Bag Module in this section.


Remote Deployment Undeployed Air Bag — Scrapped Vehicle

1. WARNINGS:


Always wear safety glasses when repairing an air bag supplemental
restraint system (SRS) vehicle and when handling an air bag module.
Failure to follow this instruction may result in personal injury.


Carry a live air bag module with the air bag and trim cover or
deployment door pointed away from your body. This will reduce the risk
of injury in the event of an accidental deployment. Failure to follow this
instruction may result in personal injury.


Remote deployment is to be carried out outdoors with all personnel
at least 6.1 meters (20 feet) away to ensure personal safety. Due to the
loud report which occurs when the air bag is deployed, hearing protection
is required. Failure to follow this instruction may result in personal
injury.

Supplemental Restraint System - B-Pillar Side Impact Sensor
Removal and Installation

Removal


NOTE: Removal steps in this procedure may contain installation details. Published: 11-May-2011

1. Make the air bag supplemental restraint system (SRS) safe.

Refer to: Standard Workshop Practices (100-00 General Information, Description and Operation).


2. WARNING: To avoid accidental deployment and possible personal injury,
the backup power supply must be depleted before repairing or replacing
any air bag supplementary restraints system (SRS) components. To
deplete the backup power supply energy, disconnect the battery ground
cable and wait for one minute. Failure to follow this instruction may
result in personal injury.

Refer to: Battery Disconnect and Connect (414-01 Battery, Mounting and Cables, General Procedures).

3. Refer to: B-Pillar Lower Trim Panel (501-05 Interior Trim and Ornamentation, Removal and Installation).




Installation

4. Torque: 12 Nm
1. To install, reverse the removal procedure.

2. If a new component has been installed, configure using Jaguar approved
diagnostic equipment.

Supplemental Restraint System - Clockspring
Removal and Installation Published: 11-May-2011


Removal

WARNINGS:


Always wear safety glasses when repairing an air bag supplemental restraint system (SRS) vehicle and when handling an
air bag module.


Carry a live air bag module with the air bag and trim cover pointed away from your body. This will reduce the risk of injury
in the event of an accidental deployment. Failure to follow this instruction may result in personal injury.


Do not set a live air bag module down with the trim cover face down. Failure to follow this instruction may result in
personal injury.


After deployment, the air bag surface can contain deposits of sodium hydroxide, a product of the gas generant
combustion that is irritating to the skin. Wash your hands with soap and water afterwards. Failure to follow this instruction
may result in personal injury.


Never probe the connectors on the air bag module. Doing so may result in air bag deployment, which may result in
personal injury. Failure to follow this instruction may result in personal injury.


Air bag modules with discolored or damaged trim covers must be replaced, not repainted.


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. If
damaged, replace the sensor whether or not the air bag is deployed.


To avoid accidental deployment and possible personal injury, the backup power supply must be depleted before repairing
or replacing any air bag supplemental restraint system (SRS) components. To deplete the backup power supply energy,
disconnect the battery ground cable and wait one minute. Failure to follow this instruction may result in personal injury.


CAUTION: Make sure the wheels are in the straight-ahead position. Failure to follow this instruction may result in
damage to the component.


NOTE: Removal steps in this procedure may contain installation details.

1. Make the SRS system safe.

Refer to: Standard Workshop Practices (100-00 General Information, Description and Operation).

2. CAUTIONS:


Make sure that special tool 211-326 is installed to the clockspring. 211-326
Locking Tool, Clockspring Special Tool(s)
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