1997 ASTON MARTIN DB7 open bonnet

Electrics
Airbag System ^^?

7.8.02.6

Renew
Passenger's Airbag Module
Read and adhere to all warnings and safety
procedures quoted at the start of this section when
working on airbag modules.
Disconnect the battery and wait for at least one
minute before proceeding with the airbag removal.
Note:
The
vehicle battery
must
be disconnected within
12
seconds
of switchingoff
the
ignition
to
avoid the alarm
siren sounding.
2. Open the passenger airbag deployment door.
3. Release four nuts and remove the airbag module.

4.
Disconnect the airbag harness multi-plug.
5. Connect and fit the new module and secure with
four nuts.
6. Refit the airbag deployment door.
Note:
The vehicle
clock and
the
window control unit will
need
resetting
after completion of
this
procedure.
7. Reconnect the battery. Switch on the ignition and
check that the airbag warning
I
ight comes on when
the ignition is switched on and extinguishes after
approximately six seconds indicating satisfactory
completion of the airbag system self tests.
6.1.23.1/6.2.10.1 Airbag
Crash
Sensors
Renew
Read and adhere to all warnings and safety
procedures quoted at the start of this section when
working on the airbag system.

1.
Disconnect the battery and wait for at least one
minute before working on the airbag system.
Note: The vehicle
battery
must be disconnected within
12
seconds
of switchingoff
the
ignition
to
avoid thealarm
siren sounding.

4.

5.
Raisethevehicleon a rampand remove the relevant
front roadwheel and wheel arch liner.
Disconnect the sensor connector and feed the
protected loom forward through the body aperture.
Open the bonnet and release two bolts securing the
crash sensor to the body.
Fit and secure the new sensor and feed the sensor
loom back through the body aperture.
Reconnect the sensor. Refit the wheel arch liner
and the roadwheel.
Note:
The vehicle
clock and
the
window control unit will
need
resetting
after completion of
this
procedure.
Reconnect the battery, switch on the ignition and
check that the airbag warning
I
ight comes on when
the ignition is switched on and extinguishes after
approximately six seconds indicating satisfactory
completion of the airbag system self tests.
6-76 September 1996

Air Conditioning
Refrigeration /s:s^°27
Refrigeration
Safety Precautions
The air conditioning system is designed to use only
Refrigerant E134A (dichlorodifluoromethane). Extreme
care must betaken NOT to use
a
methylchloride refrigerant.
The chemical reaction between methylchloride and the
aluminium parts ofthe compressor results in the formation
ofproductswhich burn spontaneously on exposure toair,
or decompose with violence in the presence of moisture.
The suitable refrigerant is supplied under the following
names.
El 34A KLEA or equivalent
Warning: Take care when handling refrigerant. Serious
damage will occur if it is allowed to come into
contact with the eyes. Always wear with goggles
and gloves when working with refrigerant
First Aid
If refrigerant should come into contact with the
eyes or
skin,
splash the eyes or affected area with
cold water for several minutes. DO NOT RUB. As
soon as possible thereafter, obtain treatment from a
Doctor or an eye specialist.
Good Practice

1.
Protective sealing plugs must be fitted to all
disconnected pipes and units.

2.
Theprotectivesealingpiugsmustremain inposition
on ail replacement components and pipes until
immediately before assembly.
3. Any part arriving for assembly without sealing
plugs in position must be returned to the supplier as
defective.

4.
It is essential that a second backing spanner is
always used when tightening or loosening all joints.
This minimises distortion or strain on components
or connecting hoses.
5. Components must not be lifted by connecting

pipes,
hoses or capillary tubes.
6. Care must be taken not to damage fins on the
condenser or evaporator matrices. Any damage
must be rectified by the use of fin combs.
7. Before assembly oftube and hosejoints, use
a
small
amount of clean new refrigerant oil on the sealing
seat.
8. Refrigerant oil for any purpose must be kept very
clean and capped at all times. This prevents the oil
absorbing moisture.
9. Before assembly the condition of joints and flares
must be examined. Dirt and even minor damage
will cause leaks at the high pressure points
encountered in the system.

10.
Dirty end fitting can only be cleaned using a cloth
wetted with alcohol.

11.
Afterremovingsealingplugsand immediatelybefore
assembly, visually check the bore of pipes and
components. Where any dirt or moisture is

discovered,
the part must be rejected.
12. Ail components must be allowed to reach room
temperature before sealing plugs are removed.
This prevents condensation should the component
be cold initially.

13.
Before finally tightening hose connections ensure
that the hose lies in the correct position, is not
kinked or twisted and will not be trapped by
subsequent operations, e.g., refitting or closing
bonnet.

14.
Check that hoses are correctly fitted in clips or
straps.

15.
The compressor must be stored horizontally with
the sump down. It must not be rotated before fitting
and charging. Do not remove the shipping plate
until immediately before assembly. Always use
new "O" ring seals in those joints that incorporate

them.
"O" ring seals should be coated with
compressor oil before fitting.

16.
Components or hoses removed must be sealed
immediately after removal.
1 7. Afterthe system has been opened the receiver-drier
must be renewed.

18.
Before
testing,
run the engine until normal running
temperature is reached. This ensures that sufficient
vacuum is available for test. For cooling tests the
engine must be running for the compressor clutch
to operate.
8-34 May 1996

^?
Air Conditioning Repair Procedures
Compressor Removal
8.1.01.1 Compressor Removal/Renewal
Procedure

1.
Open the bonnet and fit a wing cover.

2.
Depressurise the air conditioning system.
3.
6.
7.
8.
9.
Disconnect the low and high pressure hoses from
the rear of the compressor. Plug the hose ends to
prevent the ingress of dirt.
Remove the compressor pivot bolt securing nut.
Carefully separate the muffler from the compressor
and remove and discard the 'O' ring
seal.

Fit a blanking plug to the muffler and a blanking
plate to the compressor, fit and tighten the bolt that
secures blanking plate.
Raise the vehicle to working height on a ramp.
Figure 7.

10.
Slacken the compressor drive belt adjuster rod and
adjuster plate securing nuts and bolts (Fig.
1
-4, 5, 6
and 7)

11.
Slacken adjuster nut (Fig.
1
-10).

12.
Remove the nut and bolt (Fig. 1-4 and 5) from
adjuster plate (Fig. 1-3).

13.
Slacken trunnion nut and bolt (Fig.
1
-9 and 2) and
remove the adjuster rod (Fig. 1-1).

14.
Disconnect the compressor multi-plug.

1
5. Remove the compressor drive belt.

16.
Pivot the compressor away from engine, support
the compressor and remove the top pivot bolt and
lift the compressor clear of the vehicle.

17.
Removethemountingbracketsfromthecompressor.

26.
Lift the compressor up to the engine and fit the top
pivot bolt (Fig.
1
-2) from above.

27.
Attach adjustment rod loosely to the compressor

(Fig.
1
-1) with nut and bolt (Fig.
1
-6 and 7).

28.
Loosely attach adjustment plate (Fig. 1-3) to the
compressor with nut and bolt (Fig.
1
-4 and 5).

29.
Fit bolt (Fig.
1
-2) through trunnion (Fig.
1
-8) and fit
nut (Fig. 1-9) to the bolt.

30.
Fit the drive belt over the pulley, move the
compressor away from the engine to tension the
drive belt and lightly tighten the bolts and nuts.

31.
To obtain the correct tension on the drive belt
tighten adjuster nuts
(Fig.
1
-10). The belt
is
correctly
tensioned when a load of 59- 63.6 kg (130 -140 lb)
applied at the centre deflects the belt 4 mm.

32.
Ensure that all securing bolts and nuts are fully

tightened.

33.
Lowerthe vehicle to the ground.

34.
Remove the blanking plate and the blanking plugs
from the compressor.

36.
Fit new 'O' ring seals to the low and high pressure
hoses and connect them to the compressor. Fit the
retaining plate, fit and tighten the screw.

38.
Charge the air conditioning system.

39.
Remove the wing cover and close the bonnet.
May 1996 8-51

Air Conditioning Repair Procedures

Field Coil Renewal
/
Gasket Kit Renewal ffi^e^'^^
8.1.02.1 Field Coil Renewal 8.1.03.1 Renew Gasket
Kit

Procedure

1.
Open
the
bonnet
and fit a
wing cover.

2.
Depressurise
the air
conditioning system.
3. Remove
the
compressor.

4.
Remove
the
compressor drive clutch.
5. Remove
the
compressor pulley.
6. Slacken
the
field coil wire clamp screw
(Fig.
1) and

release
the
wire from
the
clamp.

10.

Remove
the
field coil retaining snap ring
and

detach
the
field
coil.

Clean
the
mating face
of the
compressor with
a

cloth moistened with
an
approved cleaning
fluid.

Position
the new
field coil
on the
compressor
and

fit
the
retaining snap
ring.

Route
the
wire
to the
compressor
and fit the
wire
clamp, tighten
the
securing screw.

11.
Fit the
compressor pulley.

12.
Fit the
compressor drive clutch.

13.
Fit the
compressor.

14.
Recharge
the air
conditioning system.

15.
Remove
the
wing cover
and
close
the
bonnet.
Data
Torque Figures
Cylinder head bolts 29.83
to 33.9 Nm.

Procedure

1.
Open
the
bonnet
and fit a
wing cover.

2.
Depressurise
the air
conditioning system.
3. Remove
the
compressor.

4.
Position
the
compressor
in a
vice, tighten
the
vice
onto
the
compressor body lugs.
5. Remove the outlet port blanking plate securing bolt
and detach
the
plate.
6. Remove
and
discard
the 'O'
ring seals from
the

outlet port.
7. Remove
the
compressor cylinder head securing

bolts,
detach
the
cylinder head.
8. Detach
the
valve plate from
the
compressor.
9. Remove
the
gaskets from
the
compressor.

10.
Remove
all
traces
of
gasket material from
the

mating surfaces
of the
cylinder head, valve plate
and cylinder block.
Figure
1.

11.
Position
new
gaskets (Fig.
1 -1
and 3) on the
valve
plate
(Fig. 1-2) and
then place
it on the
cylinder
block.
8-52 May
1996

ES3^^
Air Conditioning Repair Procedures
Valve Plate Renewal

Figure
2.

12.
Position the cylinder head (Fig. 2-1) on the cylinder
block (Fig. 2-2), fit and tighten the securing bolts in
the sequence shown in Fig. 3.
8.1.04.1 Valve Plate Renewal
Data
Torque Figures
Cylinder head bolts 29.83 - 33.9 Nm
Procedure

1.
Open the bonnet and fit a wing cover.

2.
Depressurise the air conditioning system.
3. Remove the compressor.

4.
Position the compressor in a vice, tighten the vice
onto the compressor body lugs.
5. Remove the outlet port blanking plate securing bolt
and detach the plate.
6. Remove the 'O' ring seals from the compressor
outlet port.
figure 3.

13.
Fit new 'O' ring seals in the compressor outlet port,
position the outlet port blanking plate and fit and
tighten the securing bolt.

14.
Check and top up compressor oil

15.
Refit the compressor.

16.
Recharge the air conditioning system.
Figure 1.
7. Removethecylinder head securing boltsand detach
the cylinder head (Fig. 1-1) from the cylinder block.
8. Remove valve plate
(Fig.
1
-2) from the compressor.
9. Remove all traces of gasket material from the
mati
ng
surfaces of the cy
I
i nder
head
and compressor.

10.
Apply clean refrigerant oil to the gaskets and then
position them on the valve plate.
May 1996 8-53

^2?
Air Conditioning Repair Procedures
Hose - Compressor to Evaporator/Air-Con Unit Renew
8.1.06.1 Hose-Compressor
to
Evaporator
Renewal
Procedure

1.
Open the bonnet and fit a wing cover.

2.
Depressurise the air conditioning systenn.
3. Remove the hose to evaporator valve clamping

plate,
disconnect the hose from the valve, remove
and discard the 'O' ring
seal.

4.
Fit a blanking plug to the evaporator valve. Release
the evaporator hose securing clips.
5. Remove the compressor outlet port retaining bolt.
6. Disconnect the hose from the compressor, discard
the hose complete with 'O' ring seals.
7. Connect the hose to the evaporator valve and
tighten clamp onto the hose.
8. Route the hose to the compressor, fit a new 'O' ring
seal and connect it to the compressor.
9. Position the outlet port retaining plate on the
compressor, fit and tighten the securing bolt.

10.
Refit the hose to the clips.

11.
Charge the air conditioning system.

12.
Remove the wing cover and close the bonnet.
8.2.01.1 Air Conditioning Unit Renewal

1.
Disconnect the battery earth
lead.

2.
Drain the engine coolant into a suitable container.
3. Depressurise the air conditioning system.

4.
Disconnect the high and low pressure hoses and
expansion valve from the air conditioning unit (see
expansion valve renewal).
5. Slacken the coolant hose to the heater matrix pipe
securing clips and disconnect the hoses from the
matrix. (This will require the removal of the air
intake hose for access.)
6. Remove the following items from inside the car:
front seats
underscuttle panels/knee bolsters
glove box assembly
facia trim (walnut trim)
radio and ashtray
centre console switch panel assembly
instrument panel and surround trim
steering wheel and column
facia assembly complete
hoses - distribution box to door vents
facia support frame
Details and drawings of the above operations can
be found in the electrical and trim sections.
Disconnect the vacuum hoses from the blower
motors, water valve and reservoir.
Un-clip the electrical harness from the air
conditioningunit, release theelectrical connections
and reposition the harness to allow removal of the
unit.
Displace and remove the footwell ventilator ducts
and hoses (Fig. 1-1).
May 1996 8-55