1997 ASTON MARTIN DB7 ECU

•=2?

Body and Trim
Rear Quarter Window Renewal
9.1.01.1 -
Rear
Quarter Window Renewal
Procedure

1.
Move the front seat forward to gain access.

2.
Switch on the ignition, release the roof locking
latches and lower the roof to approximately the
midway position. Switch off the ignition.
3. Remove the rear seat squab and cushion. Remove
the rear quarter trim panel.

4.
Remove the roof cylinder support bracket securing

bolts.

5. Support the roof, removethecylindertoroofsecuring
bolt. Remove the cylinder bracket.
6. Disconnectthecylinderfromthepivotand carefully
lower the roof.
7. Remove the window motor cover. Disconnect the
window motor feed wires.
Reassembly
Reassembly is the reverse of the removal procedure.
On reconnection of the motor, check the window
height as follows:

1.
Switch on the ignition and raise the rear quarter
windows.

2.
Check that the top of the glass is exactly level with
the top edge of the fully raised door window.
3. Check for
a
complete vertical seal between the rear
quarter window and the door window.

4.
If the rear window alignment is not correct, adjust
it using the procedure in the Wind Noise and
Sealing section.
5. Switch off the ignition and complete the reassembly.
6. Switch on the ignition, raise the roof and recheck
for complete sealing at the rear window top edge.
Figure 1. Window Motor Mountings
8. Release and remove the window motor finisher,
feeding the wires through the grommet.
9. Remove the window motor mounting bracket
securing bolts.

10.
Remove the motor assembly, disengaging it from
the glass.

11.
Remove the window carrier securing nuts and
special washers

12.
Remove the window
adjusters,
d isplace and remove
the window carrier.
May 1996 7-13

^^7
Body and Trim
Rear Quarter Window Lift Motor
9.1.01.4 - Rear Quarter Window Lift
Motor - Left Hand
Procedure

1.
Move the front seat forward to gain access.

2.
Switch on the ignition, release the roof locking
latches and lower the roof. Switch off the ignition.
Remove the rear seat squab and cushion. Remove
the rear quarter trim panel.
Disconnect the window motor feed wires.
Figure 1. LH Window Lift Motor Removal
5. Release and remove the window motor finisher,
feeding the wires through the grommet.
6. Remove the window motor mounting bracket
securing bolts.
7. Remove the motor assembly, disengaging it from
the glass.
8. Remove the motor to carrier securing bolts and
remove the motor.
Reassembly
Reassembly is the reverse of the removal procedure.
On reconnection of the motor, check the window
height as follows:

1.

2.

Switch on the ignition and raise the rear quarter
windows.
Check that the top of the glass is exactly level with
the top edge of the fully raised door window.
Check for
a
complete vertical seal between the rear
quarter window and the door window.
Figure 1. Rear Quarter Window Alignment

4.
If the rear window alignment is not correct, adjust
it using the procedure in the Wind Noise and
Sealing section.
5. Switch off the ignition and complete the reassembly.
6. Switch on the ignition, raise and latch the roof,
recheck for complete sealing at the rear window
top edge.
May 1996 7-15

Body and Trim
Rear Quarter Window Lift Motor '^^
9.1.01.5 - Rear Quarter Window Lift
Motor - Right Hand
Procedure

1.
Move the front seat forward to gain access.

2.
Switch on the ignition, release the roof locking
latches and lower the roof. Switch off the ignition.
3. Remove the rear seat squab and cushion. Remove
the rear quarter trim panel.

4.
Disconnect the window motor feed wires.
Figure 1. LH Window Lift Motor Removal
5. Release and remove the window motor finisher,
feeding the wires through the grommet.
6. Remove the window motor mounting bracket
securing bolts.
7. Remove the motor assembly, disengaging it from
the glass.
8. Remove the motor to carrier securing bolts and
remove the motor.
Reassembly
Reassembly is the reverse of the removal procedure.
On reconnection of the motor, check the window
height as follows:

1.
Switch on the ignition and raise the rear quarter
windows.

2.
Check that the top of the glass is exactly level with
the top edge of the fully raised door window.
3. Check for a complete vertical seal between the rear
quarter window and the door window.
A
Figure 2. Rear Quarter Window Alignment
4. If the rear window alignment is not correct, adjust
it using the procedure in the Wind Noise and
Sealing section.
5. Switch offthe ignition and complete the reassembly.
6. Switch on the ignition, raise and latch the roof,
recheck for complete sealing at the rear window
top edge.
7-16 May 1996

Body and Trim
Roof Seals - Adjustment
9.2.01.6 - Roof
Seals
- Adjustment
Seal adjustment is done in two stages. First stage -
lateral adjustment, and second stage - outward
adjustment. Seals are packed out using selected
packing strips.
Lateral Adjustment
Partially open the roof.
Front frame seal only: Remove the seal retaining

plate.
Remove the seal from the channel.
Slacken the channel securing screws and reposition
the channel as required, moving it on the slotted
screw holes (Fig 3-A). Tighten the channel securing
screws.
Apply soft soap to the seal and insert the outer seal
edge into the channel. Then press in the inner edge
to fully seat the
seal.

Refit the seal retaining plate.
Outward Adjustment
Partially open the roof.
Remove the seal retaining plate. Remove the seal
from the channel. Mark the position of the channel
for reference, release the screws and remove the

channel.

Select the appropriate packing (Figure 3-B)(see
DB7 Volante parts manual):
Rear frame seal foam strip
Front frame seal foam strip
Main column seal foam strip
Upper 'A' post seal foam strip
Note: The foam strips are for full length packing. For
packing at one end
only,
a shorter rubber
wedge
can be
used. (Fig 1-C)
Fit the foam strip/rubber wedge and channel. Align
the channel in the previously marked position. Fit
and tighten the securing screws.
Apply soft soap to the seal and insert the outer seal
edge into the channel. Then press in the inner edge
to fully seat the
seal.
Refit the seal retaining plate.
Note: It is imporrtant at all times to retain the overall
shapeoftheroofsealline(Fig4).
Wherea
leak necessitates

the
adjustment of only
one
or two
seals,
ensure
that
there
are
no
misalignments.
A more
satisfactory result
may be
obtained by adjusting the adjacent component, i.e. the
door
glass
or rear quarter glass.
The relationship between the roof seals is very
important. Two seals in very close contact will
promote leakage problems. Sealing will be far more
effective ifthe seals touch lightly or exhibit a small
air gap (Fig 4).
Figure 4. Seal Line and spacing
Figure 3. Front Frame Seal Adjustment
7-18 May 1996

Air Conditioning
Working Practices O" 15-^?
Working Practices
General
Be aware of, and comply
with,
all health and safety
requirements.
Before beginning any repair or service procedure,
disconnect the vehicle battery ground connection
and protect the vehicle from dirt or damage.
Work in a well ventilated, clean and tidy area.
Recovery and chargeequipment must comply
with,

or exceed the standard detailed in the General
Description.
Handling Refrigerant
Wear eye protection at all times.
Use gloves, keep skin that may come into contact
with refrigerant covered. If the refrigerant comes
into contactwith youreyesorskin wash the affected
area immediatelyw'ith cool water and seek medical
advice, do not attempt to treat yourself.
Avoid inhaling refrigerant vapour, it wil
your respiratory system.
irritate
Never use high pressure compressed air to flush out
a system. Under certain circumstances a
combination of HFC 134A and compressed air in
the presenceofa source ofcombustion (for instance,
welding or brazing equipment), results in an
explosion that releases toxic compounds into the
atmosphere.
The refrigerant and CFC 12 must never come into
contact with each other
as
they form an inseparable
mixture that can only be disposed of by incineration.
Do not vent refrigerant directly into the atmosphere,
always use approved recovery equipment.
Refrigerant is costly but it can be recycled. Clean
the refrigerant, using the recovery equipment and
reuse it.
Carry out LeakTestsonly with an electronic analyser
dedicated to Refrigerant El 34A.
Do not attemptto guess the amount of refrigerant in
a system, always recover it and recharge with the
correct charge weight. Do not depress the charge or
discharge port valves to check for the presence of
refrigerant.
Handling Lubricating Oil
Avoid breathinglubricantmist,itwillcauseirritation
to your respiratory system.
Always decant fresh oil from a sealed container. Do
not leave oil exposed to the atmosphere for any
reason other than to fill or empty a system; PAG oil
is hygroscopic (it absorbs water) and iscontaminated
rapidly by atmospheric moisture.
Following the recovery cycle do not reuse the oil
when it has been separated from the refrigerant;
dispose of the oil safely.
System Maintenance
Do not leave the system open to the atmosphere. If
a unit or part of the system is left open for more than
five minutes, it is advisable to renew the receiver-
dryer. There is not a safe period in which work is to
be carried out. Always plug pipes and units
immediately after disconnection and only remove
plugs when re-connecting.
If replacement parts are supplied without transit
plugs and seals do not use the parts. Return them to
your supplier.
Diagnostic equipment for pressure, mass and
volumeshouidbecalibrated regularly and certified
by a third party organisation.
Use extreme care when handling and securing
aluminium fittings, always use a backing spanner
and take special care when handlingtheevaporator.
Use only the correct or recommended tools for the
job and apply the manufacturer's torque
specifications.
Keep the working area, all components and tools

clean.

8-8 May 1996

Air Conditioning
Temperature Distribution System
The Control Panel (Fig. 4) contains:
• Fan speed-defrost rotary switch (Mode-Switch),
• Air Conditioning Function Switch
• Temperature differential rotary control
• Temperature rotary control,
The control panel relays information to the ECM.
Figure 4.
Fan Speed Control (Mode Switch)
The rotary switch controls airflow from the blower motors. The switch has five positions: 3C, 1, 2,3 and DEFROST.
«» The system is not operational; a residual signal is sent to the Electronic Control Module (ECM)
to ensure that the blower flaps are closed to prevent outside air from entering the system.

1,
2,3 Selection information is relayed to the ECM. Signals are also relayed to the ECM from the
temperature selector feedback circuits and various sensors. Fan speed is steplessly controlled
by the ECM, within the ranges 1, 2 and 3.
DEFROST the fans operate at maximum speed, front screen vents open fully, lower flaps close fully and
maximum output is directed to the windscreen (there may be a delay of up to 30 seconds from
selection to execution of this function).
Face Level Temperature Differential
This control is used to vary the temperature difference between the air coming through the face vents and that coming
through the lower vents into the footwell.
Temperature Rotary Control
This is used to preset the in car heat level in either automatic or manual mode. There are three temperature sensors
located in the system:
• Exterior ambient
• In-car
• Evaporator.
An input voltage is supplied to the sensors from AC4-13 of the control module. The temperature sensing signal from
the sensors is transmitted to the control module via AC4-4 and AC2-4 respectively. The sensors are semiconductor
devices which provide a voltage output proportional to the sensed temperature.
8-10 May 1996

Air Conditioning //~-->> ^/zz:^^ • ^ ^
General Svstem Procedures ' —"^ ^ '^ General System Procedures
From the condenser the liquid passes into the Receiver-Drier which has three functions:
• Storage vessel for varying system refrigerant demands.
• Filter to remove system contaminants.
• Moisture removal via the desiccant.
With the passage through the receiver-drier completed the, still high pressure liquid refrigerant, enters the Expansion
Valve where it is metered through a controlled orifice which has the effect of reducing the pressure and temperature.
The refrigerant, now in a cold atomised state, flows into the Evaporator and cools the air which is passing through
the matrix.
As heat is absorbed by the refrigerant it once again changes state, into a vapour, and returns to the compressor for
the cycle to be repeated (Fig. 5).
There is an automatic safety valve incorporated in the compressor which operates should the system pressure be
in excess of
41
bar. The valve re-seats when the pressure drops below 35 bar.
Note: The division of HIGH and LOW side is simply the
system pressure
differential created by the
compressor
discharge

(pressure),
suction
(inlet)
ports and
the
relative inlet and outlet
ports
of the
expansion
valve.
This
differential is critical to
system

fault
diagnosis
and efficiency checks.
System Protection
The trinary pressure switch, located in the liquid line, cuts electrical power to the compressor clutch if the system
pressure is outside of the range of 2 Bar
(1
st Function) to 27 Bar (2nd Function). The third function is to switch on
the cooling fans when pressure exceeds 20 bar.
General System Procedures
Leak Test
Faults associated with low refrigerant charge weight and low pressure may be caused by leakage. Leaks traced to
mechanical connections may be caused by torque relaxation or joint face contamination. Evidence of oil around
such areas is an indicator of leakage. When checking for non visible leaks use only a dedicated Refrigerant El 34A
electronic analyser and apply the probe all round the joint connection. Should a leak be traced to a joint, check that
the fixing is secured to the correct tightening torque before any other action is taken.
Do not forget to check the compressor shaft seal and evaporator.
Note: Never
use
a dedicated
CFC 12
or
naiced
flame type
analyser.

Charge Recovery (System Depressurisation)
The process of refrigerant recovery depends on the basic characteristics of your chosen recovery-recycle-recharge
equipment, therefore, follow the manufacturers instructions carefully. Remember that compressor oil may be drawn
out of the system by this process, take note of the quantity recovered so that it may be replaced.
CAUTION: Observe all relevant safety requirements.
• Do not vent refrigerant directly to atmosphere and always use approved recovery-recycle-recharge
equipment.
• Wear suitable eye and skin protection.
• Do not mix the refrigerant with CFC 12.
• Take note of the amount of recovered refrigerant, it indica
tes the
state of the
system
and
thus the
magnitude
of any problem.
8-12 May 1996

Air Conditioning
Compressors ^?
Evaporator
Figure 3.
Receiver-Drier
The receiver drier (Fig. 1) accepts high pressure
warm refrigerant liquid from the condenser and
del ivers it via an expansion valve to the evaporator.
It contains a quantity of molecular sieve desiccant
to remove moisture from the refrigerant, and
a
fi Iter
to removecontaminants.lt also
a
providesa reservoir
of refrigerant for the evaporator under varying
operating conditions.
The evaporator consists of a refrigerant coil mounted
in a series of thin fins to provide a maximum
amount of heat transfer in a minimum amount of

space.
It is housed in the air conditioning unit and
all air entering the system passes across its
coil.

The evaporator receives refrigerant from the
thermostatic expansion valve as a low pressure
cold atomised liquid. As this cold liquid passes
through the evaporator coils, it absorbs heat from
the surrounding air and changes into
a
low pressure
warm vapour.
Expansion Valve
The expansion valve is the dividing point between
the high and low pressure sides of the system. It
automatically meters high pressure, warm liquid
refrigerant via a metering orifice into the low
pressure, cold side of the evaporator matrix. The
valve senses outlet pipe temperature, inlet pipe
pressure and regulates the flow of refrigerant into
the evaporator to ensure that only vaporised
refrigerant appears at the outlet.
Figure 1.
8-36 May 1996