Part 3
STANDARD WORKSHOP PRACTICES
SRS harness and connectors
Always observe the following precautions with regards to SRS system electrical wiring:
- Never attempt to modify, splice or repair SRS wiring.
- Never install electrical equipment such as a mobile telephone, two-way radio or in-car entertainment system in such a way that it could generate electrical interference in the air bag harness. Seek specialist advice when installing such equipment.
NOTE: SRS wiring can be identified by a special yellow outer sleeve protecting the wires (black with yellow stripe protective coverings are sometimes used).
WARNING: Always make sure SRS wiring is routed correctly. Be careful to avoid trapping or pinching the SRS wiring.
WARNING: Do not leave the connectors hanging loose or allow SRS components to hang from their harnesses. Look for possible chafing points.
Impact sensors - inspection
After any degree of side or frontal body damage, inspect the impact sensors. Replace a sensor if there is any sign of damage.
CAUTION: Take extra care when painting or carrying out bodywork repairs in the vicinity of the impact sensors. Avoid direct exposure of the impact sensors or link harnesses to heat guns, welding or spraying equipment. Take care not to damage sensor or harness when reinstalling components.
Clockspring
CAUTION: Always follow the procedure for installing and checking the clockspring as instructed in the SRS repairs section. Comply with all safety and installation procedures to make sure the system functions correctly. Observe the following precautions:
- Do not unlock and rotate the clockspring when it is removed from the vehicle.
- Do not turn the road wheels when the clockspring is removed from the vehicle.
- Always make sure the clockspring is removed and installed in its central position and with the front road wheels in the straight ahead position - refer to SRS repair section for the correct removal and installation procedure.
- If a new clockspring is being installed, make sure the locking tab holding the spring's rotational position is not broken; units with a broken locking tab must not be used.
Air bag and pre-tensioner deployment
WARNING: During deployment parts of the air bag module become hot enough to burn you. Wait 30 minutes after deployment before touching the air bag module.
Deployment procedures and precautions as detailed in this manual should be strictly adhered to. Only personnel who have undergone the appropriate training should undertake deployment of air bag and pre-tensioner modules. The following precautions must be complied with:
- Only use deployment equipment approved for the intended purpose.
- Deployment of air bag/pre-tensioner modules must be performed in a well ventilated area which has been designated for the purpose.
- Make sure air bag/pre-tensioner modules are not damaged or ruptured before attempting to deploy.
- Where local legislation exists, notify the relevant authorities of intention to deploy air bag and pretensioner units.
- When deploying air bag pre-tensioner units, make sure that all personnel are at least 15 meters (45 feet) away from the deployment zone.
- Make sure deployment tool is connected correctly, in compliance with the instructions detailed in the SRS section of this manual. In particular, make sure deployment tool is NOT connected to battery supply before connecting to air bag module connector.
- When deploying safety belt pre-tensioners, make sure pre-tensioner unit is secured correctly to the seat.
- When removing deployed air bag modules and pre-tensioner units, wear protective clothing. Use gloves and seal deployed units in a plastic bag.
- Following deployment of any component of the SRS system within the vehicle, all SRS components must be replaced. DO NOT re-use or salvage any parts of the SRS system.
- Do not lean over an air bag module when connecting deployment equipment.
If a vehicle is to be scrapped, undeployed air bag modules and pre-tensioner units must be manually deployed. In this case air bags can be deployed in the vehicle. Before deployment, make sure the air bag module is secure within its correct mounting position. Deployment of the driver air bag in the vehicle may damage the steering wheel; if the vehicle is not being scrapped, deploy the module outside of the vehicle.
SRS Component Replacement Policy
CAUTION:
- The Restraints Control Module (RCM) will log a crash fault after every impact which is severe enough to cause air bag deployment. It is possible to have three crashes/impacts logged after one event where, for example, a front, side and rollover has occurred. After the third fault is logged, the SRS warning lamp will be illuminated and the restraints control module (RCM) must be replaced.
- The SRS side/front impact sensor(s) must be replaced if there are any signs of physical damage or if the restraints control module (RCM) is registering a fault.
The following information details the policy for replacement of SRS components as a result of a vehicle accident.
Impacts which do not deploy the air bags or pre-tensioners
Check for structural damage in the area of the impact paying particular attention to bumper armatures, longitudinals and bracketry.
Impacts which deploy the air bags or pre-tensioners
The replacement and inspection policy is dependent on the type and severity of the crash condition. The following guidelines are the minimum that should be exercised as a result of the deployment of specific SRS components.
Check for structural damage in the area of impact paying particular attention to bumper armatures, longitudinals and bracketry.
Front Air Bag Deployment - Driver and Passenger
CAUTION: If the front air bags are deployed, the following components must be replaced:
- Driver air bag module
- Passenger air bag module
- Fly leads (where applicable) connecting front air bag modules to SRS harness
- Front safety belt buckle pre-tensioner
- Rear safety belt pre-tensioners - if installed
- Driver safety belt retractor - if installed
- Clockspring
- Any front impact sensors that have been physically damaged or if a fault is being registered
- Restraints Control Module (RCM) if the three crashes/impacts have been stored
Additionally, the following items must be inspected for damage and replaced as necessary:
- Front passenger safety belt retractor and webbing, tongue latching function, 'D' loop and body anchorage point
- Rear safety belt buckles, webbing, buckle covers, body anchorage points and tongue latching function
- Instrument panel moulding adjacent to passenger air bag module
- Steering wheel
- Front seat frames and head restraints
- Steering column - if adjustment is lost or if there are signs of collapse
- Safety belt height adjusters
- Rear safety belts
Side Air Bags
CAUTION: If the side air curtains are deployed, the following components must be replaced on the side of the vehicle on which the deployment occurred:
- Side air curtains
- Any side impact sensors that have been physically damaged or if a fault is being registered
- Restraints Control Module (RCM) if the three crashes/impacts have been stored
Additionally, the following items must be inspected for damage and replaced as necessary:
- Front passenger safety belt retractor and webbing, tongue latching function, 'D' loop and body anchorage point
- Rear safety belt buckles, webbing, buckle covers, body anchorage points and tongue latching function
- Instrument panel moulding adjacent to passenger air bag module
- Steering wheel
- Front seat frames and head restraints
- Steering column - if adjustment is lost or if there are signs of collapse
- Safety belt height adjusters
- Rear safety belts
Side Air Bags
CAUTION: If the side air curtains are deployed, the following components must be replaced on the side of the vehicle on which the deployment occurred:
- Side air curtains
- Any side impact sensors that have been physically damaged or if a fault is being registered
- Restraints Control Module (RCM) if the three crashes/impacts have been stored
Additionally, the following items must be inspected for damage and replaced as necessary:
- Front safety belts, retractors and webbing, tongue latching function, 'D' loop and body anchorage points
- Rear safety belt buckles, webbing, buckle covers, tongue latching function, and body anchorage points
- Front seat frame and head restraints
- Door trim casing
- Safety belt height adjusters
- Rear safety belts
Side Air Curtain modules
CAUTION: If the side air curtain modules are deployed, the following components must be replaced on the side of the vehicle on which the deployment occurred:
- Side air curtain modules
- Link lead between side air curtain gas generator and restraints control module (RCM) harness
- Side air curtain module retaining clips
- Internal trim finisher
- Front safety belt buckle pre-tensioners
- Any side impact sensors that have been physically damaged or if a fault is being registered
- Restraints Control Module (RCM) if the three crashes/impacts have been stored
Additionally, the following items must be inspected for damage and replaced as necessary:
- Headlining
- Component mounting brackets
- Front safety belts, retractors and webbing, tongue latching function, 'D' loop and body anchorage points
- Rear safety belt buckles, webbing, buckle covers, tongue latching function, and body anchorage points
- Adjacent trim components
- Safety belt height adjusters
Rear impacts
CAUTION: If the safety belt pre-tensioners are deployed during a rear impact, the following components must be replaced:
- Safety belt pre-tensioners
- Front and rear safety belt retractors deployed during the impact
- Restraints Control Module (RCM) if the three crashes/impacts have been stored
Additionally, the following items must be inspected for damage and replaced as necessary:
- Safety belt height adjusters
- Front safety belts, retractors and webbing, tongue latching function, 'D' loop and body anchorage points
- Rear safety belt buckles, webbing, buckle covers, tongue latching function, and body anchorage points
Air Conditioning (A/C) System Precautions
The A/C system contains fluids and components which could be potentially hazardous to the service engineer or the environment if not serviced and handled correctly. The following guidelines are intended to alert the service engineer to potential sources of danger and emphasise the importance of ensuring the integrity of the A/C operating conditions and components installed to the vehicle.
Where necessary, additional specific precautions are detailed in the relevant sections of this Manual and also in the Health and Safety Section. These precautions must be referred to prior to commencing repair operations.
The refrigerant used in the A/C system is HC-134a (Hydrofluorocarbon) R134a.
WARNING:
- Servicing must only be carried out by personnel familiar with both the vehicle system and the charging and testing equipment. All operations must be carried out in a well ventilated area away from open flame and heat sources.
- R134a is a hazardous liquid and when handled incorrectly can cause serious injury. Suitable protective clothing, consisting of face protection, heat proof gloves, rubber boots and rubber apron or waterproof overalls, must be worn when carrying out operations on the A/C system.
Remedial actions
WARNING: Due to its low evaporating temperature, R134a must be handled with care. R134a splashed on any part of the body will cause immediate freezing of that area. Also, refrigerant cylinders and replenishment trolleys when discharging will freeze skin to them if contact is made.
If an accident involving R134a should occur, conduct the following remedial actions:
- If liquid R134a enters the eye, do not rub it. Gently run large quantities of eye wash over affected eye to raise the temperature. If an eye wash is not available, cool, clean water may be used to flush the eye. After rinsing, cover the eye with a clean pad and seek immediate medical attention.
- If liquid R134a is splashed onto the skin, run large quantities of water over the affected area to raise the temperature. Implement the same action if the skin comes in contact with discharging cylinders. Wrap the contaminated body parts in blankets (or similar materials) and seek immediate medical attention.
- If the debilitating effects of inhalation of R134a vapor are suspected, seek fresh air. If the affected person is unconscious, move them away from the contaminated area to fresh air and apply artificial respiration and/or oxygen and seek immediate medical attention.
Service precautions
Observe the following precautions when handling components used in the system:
- A/C units must not be lifted by their hoses, pipes or capillary lines.
- Hoses and lines must not be subjected to any twist or stress; the efficiency of the system will be impaired by kinks or restrictions. Make sure that hoses are correctly positioned before tightening couplings, and make sure that all clips and supports are utilized.
- Flexible hoses should not be positioned closer than 100 mm (4.0 in) to the exhaust manifold unless protected by heat shielding.
- Completed assemblies must be checked for refrigeration lines touching metal panels. Any direct contact of components and panels may transmit noise and so must be eliminated.
- The appropriate torque wrench must be used when tightening refrigerant connections to the stipulated value. An additional spanner must be used to hold the union to prevent twisting of the pipe when tightening connections.
- Before connecting any hose or pipe, make sure that refrigerant oil is applied to the seat of the new O-rings, BUT NOT to the threads of the connection.
- All protective plugs or caps must remain in place in the component until immediately prior to connection.
- Make sure components are at room temperature before uncapping/unplugging, to prevent condensation of moisture from the air that enters it.
- When disconnecting, immediately plug or cap all pipes to prevent ingress of dirt and moisture into the system.
- Components must not remain uncapped/unplugged, if a system has been left uncapped/unplugged for 24 hours or longer, a new receiver/drier must be installed.
- The receiver/drier contains desiccant which absorbs moisture. It must be positively sealed at all times. A receiver/drier that has been left uncapped for longer than 24 hours must not be used; install a new unit.
- The receiver/drier should be the last component connected to the system to make sure optimum dehydration and maximum moisture protection of the system.
- Whenever a component of the refrigeration system is replaced, it will also be necessary to install a new receiver/drier unit.
- Use alcohol and a clean lint-free cloth to clean dirty connections.
- Make sure that all new parts installed are marked for use with R134a.
- When a major repair has been completed, a leak test should be conducted; refer to the Repairs Section of this manual for the correct procedure.
Refrigerant oil
CAUTION: Refrigerant oil (ND-8 PAG) easily absorbs water and must not be stored for long periods. Do not pour unused refrigerant oil back into the container. Always use an approved refrigerant oil.
When replacing components in the system, drain the refrigerant oil from the component being replaced into a graduated container. On assembly, add the quantity of refrigerant oil drained to the new component - See Compressor Replacement in this Section.
A/C Compressor
A new compressor is sealed and pressurized with Nitrogen gas. When installing a new compressor, slowly release the sealing cap; gas pressure should be heard to vent as the seal is broken.
CAUTION: A new compressor should always be sealed and should be pressurized with nitrogen gas. To avoid possible oil loss, release the sealing cap(s) slowly. Do not remove the cap(s) until immediately prior to connecting the pipes to the compressor.
Rapid refrigerant discharge
If the A/C system is damaged as a result of an accident and the system is punctured, the refrigerant will discharge rapidly. The rapid discharge of refrigerant will also result in the loss of most of the oil from the system. The compressor must be removed and all the remaining oil in the compressor drained and refilled as instructed in the air conditioning section of this manual.
Precautions for refrigerant recovery, recycling and recharging
When the A/C system is recharged, any existing refrigerant is first recovered from the system and recycled. The system is then charged with the required weight of refrigerant and volume of refrigerant oil.
WARNING: Refrigerant must always be recycled before re-use to make sure that the purity of the refrigerant is high enough for safe use in the system. Recycling should always be carried out with equipment which is design certified by Underwriter Laboratory Inc.. for compliance with SAE J1991. Other equipment may not recycle refrigerant to the required level of purity.
CAUTION:
- A R134a Refrigerant Recovery Recycling Recharging Station must not be used with any other type of refrigerant. Refrigerant R134a from domestic and commercial sources must not be used in motor vehicle systems.
- The system must be evacuated immediately before recharging commences. Delay between evacuation and recharging is not permitted.
A/C Compressor Replacement
A new compressor is supplied filled with a full charge (X cu.cm.) of refrigerant oil.
A calculated quantity of oil must be drained from the new compressor before installation. To calculate the quantity of oil to be drained:
- Remove the drain plug from the old compressor.
- Invert the compressor and gravity drain the oil into a calibrated measuring cylinder. Rotate the compressor clutch to make sure the compressor is completely drained.
- Note the quantity of oil drained (Y cu.cm.).
- Calculate the quantity of oil to be drained from the new compressor using the following formula:X cu.cm. - (Y cu.cm. + 20 cu.cm.) = Q cu.cm.
- Remove the drain plug from the new compressor and drain Q cu.cm. of oil. Install and tighten the compressor drain plug.
- Weight quoted is the maximum weight possible for vehicles in this model range; weights may be less for certain variants depending upon trim level, territorial requirements etc.
