1997 ASTON MARTIN DB7 change time

3^?
Electrics
Rear Lamp Cluster / Central Locking System / Door Lock Motors
6.7.02 Rear Lamp Cluster Door Mounted Components
Procedure

1.
Remove the rear lamp cluster inner cover.

2.
Release the boot rear liner
3. Release the two nuts and one screw securing the
rear lamp surround and remove the surround.
Figure 7. Rear Lamp Cluster

4.
Disconnect the rear lamp cluster multi-plug.
5. Remove six nuts from the rear of the assembly and
lift out the lamp cluster.
Central Locking System
Description
Thecentral locking system consistsofmotoroperated lock
actuators in both doors, the boot and the fuel flap
mechanism. The central locking control module is located
inside the drivers side 'A' post.
Each motordriven lock actuator incorporatesa microswitch
which will signal a change of state when any motor runs
to drive the actuator. The microswitches are of the
changeover type and provide an earth for the lock or
unlock signals to the control unit.
The two door lock inputs to the control unit are connected
together so that operation of either door lock with the
ignition key will simultaneously operate the other door
lock. Similarly, the unlock inputs to the control unit are
also connected together for simultaneous operation.
The boot will remain locked or will be unlocked
simultaneously with the doors dependant on the boot lock

position.
With the boot key turned clockwise, the boot
lock operates in unison with the doors. With the boot key
turned anticlockwise, the boot lock cannot be unlocked
using the central locking system.
The boot can be opened at any time using the ignition key
irrespective of the central locking status.
6.7.03 Door Central Locking Motors
Procedure

1.
Remove the door inner panel.

2.
Disconnect two plugs on the central locking motor
unit and one plug on the door closed switch.
3. Release the interior door catch operating rod from
its guide clips and detach it from the lock
mechanism.

4.
Disconnect the outer lock operating rod.
5. Remove three lock securing screws from the door
rear edge.
6. Remove the motor and lock through the access

hole.

7. Remove the motor securing screws and remove the
motor from the lock assembly.
May 1996 6-13

Electrics
Component Index Sheet 3 - 97
MY

Component
Name
Interior Light - Rear RH
Key Solenoid
Key-In Warning Switch
Low Coolant Signal Transmitter
Low Level Sensor (Screenwash)
Map Reading Light
Mass Airflow (MAF) Sensor
Multifunction Module
Number Plate Lamp - LH
Number Plate Lamp - RH
Oil Pressure Transducer (EOP)
PATS Module
PATS Transceiver
Performance Mode Switch
Powertrain Control Module (PCM)
Purge Cannister Vent Valve
Radiator Switch
Radio
Radio Aerial
Radio Telephone Connector
Radio Tweeter (LH)
Radio Tweeter (RH)
Rear Lamp - LH
Rear Lamp - RH
Relay - Air Conditioning
Relay - Air Conditioning W.O.T.
Relay - Air Pump
Relay - Auxiliary Load (
Relay - Auxiliary Load (
Relay - Courtesy Lights (
Relay - Clutch (
Relay-Day Time Running (
Relay - Drivers Seat Heater (
Relay - Fan Change-Over (
Relay - Fan Run On
Relay - Front Fog Lamps
Relay - Fuel Pump 1
Relay - Fuel Pump 2
Relay - Gearbox Failure Warning
Relay - Glass Drop
Relay - Hazard Unit
Relay - Headlamp Dipped Beam
Relay- Headlamps
Relay - Heated Front Screen Control
Relay - Heated Rear Window
Relay - Hood Down (Roof Down)
Relay - Hood Up (Roof Up)
Relay - Horn
Relay - indicator Unit (Flasher Unit)
Relay - Left Quarter Light Up
Relay - Left Quarter Light Down
Relay - Load
Relay- Main
Relay - Main Beam
Relay - Passenger Seat Heater
Component
Location
14-6
14-4
14-4
7-13
14-3
10-9
14-1
6-1
14-8
14-7
15-3
4-9
15-4
6-8
4-1
15-7
15-2
5-1
5-4
8-3
5-2
5-2
15-8
15-6
see relay location chart) di II II II
II II II II
II II II II
11 II II II
II II II II
II II II II
II II II II
II II II II
II II II II
11 II II II
II II II II
II II II II
II II It II
II II II II
11 II II II
II II II II
II II II II
II II II II
II II II II
II It II II
II II II II
11 II II II
II II II II
11 II II II
11 II II II
II II II II
II II II II
II II II II
II II II II
II II II II
Circuit
Reference
16-A2
9-D3
9-D3
12-82
3-A2
8-A4
5-D2
12-B5
16-D6
16-C6
5-C4
12-B1
9-C2
4-A2
6-B5
15-B3
5-D1
10-B3
16-C2
16-B5
8-A3
12-C2
15-B6
16-D2
3-A4
3-A5
1-A5
9-D1
12-D1
9-D1
1-B5
1-A6
23-D3
3-C4
3-A3
) 1-B5
) 17-A2
) 17-A4
9-D2
) 12-C1
) 8-C3
2-A2
) 2-B2
) 12-D3
) 8-C4
) 19-A2
) 19-A3
) 1-85
) 8-C3
) 18-A5
) 18-A5
) 12-D1
) 12-D2
) 2-83
) 24-D3
September 1996 6-45

5^^?
Electrics
Seat Belt Pretensioner
The Seat Belt Pretensioner System (where fitted)
Description
The DB7 seat belt pretensioner system operates the drivers seat belt pretensioner in conjunction with the Airbag

system.
The seat belt pretensioner control module is located under the right hand seat, beside the right hand seat
control module.
The pretensioner control module calculates changes in vehicle speed using an input signal from an accelerometer.
When a collision is detected (Rapid reduction in vehicle speed) and the safing sensor in the airbag system is also

activated,
the pretensioner charge
is
fi red usingelectrical energy stored in a capacitor within the pretensioner control
module. Firing of the pretensioner charge applies additional tension to the drivers seat belt.
The airbag and seat belt pretensioner systems share the SRS (Airbag) warning lamp. Any fault detected by the
pretensioner control module is indicated by constant illumination ofthe
SRS
(Airbag) warning lamp. Flashing of the
SRS warning lamp indicates a fault in the airbag system.
Should both systems develop faults, the pretensioner system will permanently illuminate the warning lamp. This
would mask the airbag system warning indication. Therefore, rectify the pretensioner fault and then retest for faults
in the airbag system
The pretensioner control module can log up to 10 diagnostic trouble codes together with a time since each fault was
alerted to the driver. Each
fau It
wi
11
be identified as 'Permanent' or 'Intermittent' on the PDU diagnostic trouble codes

screen.

System Connections
DB7 is fitted with an Autoliv ECS or RC5 Pretensioner Control Module. The Pretensioner Control Module has an 18
pin connector featuring six shorting bridges. The mating halves of the connector may be securely locked using a
double mechanical locking system.
The following pins on the control module connector are used in the Aston Martin seat belt pretensioner system:
Pin 1 Ground
' ' "L Pin 2 Airbag Warning Lamp
Pin 11 Drivers airbag positive
Pin 12 Drivers airbag negative
Pin 14 Serial communications
Pin 15 12 volt positive feed
Case Ground

15.
rrj ^
ooooooooooooooo
16 illn
^
Note: Pins
1
-2, 3 -4, 5 -6, 7 -8,9 -
10
and 11-12
are
shorted
together
by internal shorting links within the connector when
it
is
disconnected.
The
short circuits may
be
temporarily
overcome
for fault analysis
purposes
by inserting
a
suitable non-metallic

cheater
(the
sBfTiG
size
3s
the
p€gs
in the controller connector) into the rectsngul^r hole opposite the relevsnt p3ir of pins.
September 1996 6-101

y/--^^^^3^
'—-p "^ Body and Trim
Roof Description
Volante Roof
Description
The system comprises an electrically driven hydraulic pump and two hydraulic rams for raising and lowering the

roof.
The pump is powered via two heavy duty changeover relays. Two further pairs of changeover relays power
the rear quarter windows (one pair for each window). The roof hydraulic pump is protected by a 30A fuse, the
windows by circuit breakers.
An electronic control module (ECM) is actuated by the roof switch on the centre console. The ECM controls the
operation of
both
the roof
and
rear quarter window circuits
so
that they can only be operated in
a
pre-programmed

manned.
When in operation, the ECM provides signals to the roof and to the rear quarter windows.
When the roof
switch
is moved into the open (Roof Down) position, the roof
and
rear windows move together until
approximately four seconds has elapsed. At this time, the ECM will remove power from the rear window circuits,
leaving the roof motor running. The roof motor will stop after 12 seconds (i.e. a further 8 seconds after the rear
window motors stop).
The signals will be removed from the rear window relay after 4 seconds and from the roof relay after 12 seconds
if the roof switch is held in either position for longer than 12 seconds.
In order to comply with legislation, the following features are built into the system:
If the roof switch is operated in either direction and then released before that operation is complete, the roof and
rear quarter windows will stop immediately. If, whilst the system is in operation, the ignition switch
is
turned to the
off position, the system will immediately stop.
If the roof switch is pressed again after pausing during a roof movement, the timing sequence will be as follows:

1.
If the previous direction is selected, the timing recommences from where it left off and will continue to
completion. If the ignition has been turned off, the timing will start from the beginning of its cycle.

2.
If theoppositedirection
is
selected,
the timing sequence will commence
from the beginning
of the newly selected
direction and continue to completion.
Roof and Rear Quarter Light Control
The following diagrams show the component location and the electrical control for the roof and rear quarter light
systems.
May 1996 7-7

Air Conditioning
System Fault Diagnosis ^=2?
System Fault Diagnosis
Probable causes of faults can be found by comparing actual system pressures, registered on the manifold gauge set
or recovery-recharge-recycie station, and the pressure to temperature relationship graphs found on the previous

page.
The chart below shows the interpretation that may be made by this difference. The 'Normal' condition is that
which is relevant to the prevailing ambient and evaporator temperatures.
Note: If erratic or
unusual gauge movements
are experienced, check the equipment
against a
known manifold
gauge
set.

Low Side
Normal
Gauge
Normal to low
Low
Low
Low
Low
High
High
High Side Gauge
Normal
Normal
Low
Low
Low
Normal to high
Low
High
High
Fault Finding
High
Symptom
Discharge air initially cool
then warms up
As above
Discharge air slightly cool
Discharge air warm
Discharge air slightly cool or
frost build up at expansion
valve
Discharge air slightly cool
Compressor noisy
Discharge air warm and high
side pipes hot
Discharge air warm
Sweating or frost at evaporator
Diagnosis
Moisture in system
As above
HFC 134A charge low
HFC 134A charge very low
Expansion valve stuck closed
Restriction in High side of system
Defective reed valve
HFC 134A charge high or
condenser malfunction
Expansion valve stuck open
Caution:
The microprocessor is extremely sensitive
and should only
be tested
using
a
digital multimeter with no
less
than a 3.5
digit display and a
resistance
of no
less than
2 M
ohms.
The use
of any other form of multimeter will
damage the microprocessor

irreparably.
Note: Always allow time for the
servo
motors and blower motors to come to a
rest
before starting a
check.

The car should be in a workshop and the ambient
temperature
should
be
stable
e.g.
24''C
(75°F)
for at
least
30 minutes before
commencing the automatic
check.

At 24°C the
sensor
voltage is
2.972
V
± 2 mV.
The
rate of
change
is lOmVper
1
°C.

Unless
stated
otherwise,
all
checks
are carried out at the ECM
test plugs

Mode Switch: Off Ignition Switch: Aux 2
Signal Pin No.
Battery supply 1
Recirc input 9
Earth-ground 2
Earth-ground 6
Earth-ground 10
Earth-ground 38
Earth-ground 45
From mode switch 44
To mode switch 12
Voltage
n to 14v
0to2V
0 to 40mV
0 to 40mV
0 to 40mV
0 to 40mV
0 to 40mV
0 to 12V
10 to 13.3V
8-30 May 1996

Air Conditioning
Refrigerant Recovery and Recycling ^=2?
Recovery Procedure
Hote:
Run the
air-conditioning
system
for
a
few
minutes
before starting the
recovery
procedure as
this will
enable

more refrigerant to be recovered. Turn the
system
off
before
starting
the procedure.

1.
Attach the red (high side) hose oftheunittothe high
side fitting of the system on the vehicle then fit the
blue (low side) fitting to the low side on the vehicle.
Note: Make sure that the Air conditioning
system
has
pressure in it before beginning the recovery
process;
if
there is no
system
pressure there is no refrigerant to

recover.
Also
make sure that the
oil
drain
valve
is
closed.

2. Open both the high and low side valves on the
control panel.
3. Open the red CAS (vapour) valve and the blue
LIQUID valve on the tank.

4.
Turn on the MAIN POWER switch.
5. Press the RECOVERY key on the key-pad. The
display shows that the unit in the RECOVER mode
and AUTOMATIC cycle. After the compressor starts
the display shows the weight of refrigerant being

recovered.
The compressor shuts off automatically
when the recovery is complete and the display
shows the message 'CPL' and the final weight of the
recovered refrigerant.
6. Wait for five minutes and watch the manifold
gauges for a rise above 0. If a rise occurs press the
HOLD/CONT key. Repeat as needed until the
system pressure holds for two minutes.
Note: Drain the oil
separator
after
each
job.
7. Slowly open the oil drain valve and drain the oil
into the oil catch bottle. When all the recovered oil
has completely drained close the valve.
8. Replace oil lost during the recovery procedure by
measuringthe amount of oil inthe catch bottle and
adding the same amount of new oil to the system.
Note:
Dispose
of the
recovered
oil in an approved way.
9. When the recovery tank is full the compressor is
shut off and the display shows the message FULL.
Evacuating and Recycling the Refrigerant

1.
Open the red (high side) and the blue (low side)
valves on the unit and open the red GAS (vapour)
valve and the blue LIQUID valve on the tank.

2.
Enter the required time using the key-pad, press
enter,thedisplayshowstheenteredtime in minutes.
3. Start the vacuum pump by pressing the VACUUM
KEY again. The recycling process begins
approximately five seconds after the vacuum pump
starts and the message RECYCLE is displayed.
Note: If the vacuum pump
has
run for ten hours or
over

without an oil change the
message
OIL
flashes
on the
display.
Change
the pump oil and
then press
the
SHIFT/

RESET key and
the
zero key to
reset the
oil
change
timer
to zero.
The digital display counts down the evacuation

time.

4.
Check for non-condensibles after five minutes

recycling.
Ifthegauge needles are more than lOpsi
apart purge the non-condensibles from the tank by
open
i ng
the purge valve on the back of the
un
it and
continue to bleed until both needles show the same

reading.

The vacuum sequence continues until the
programmed time has elapsed at which point the
message CPL is displayed.
5. If the moisture indicator turns green recharge with
refrigerant.
or
5. If the moisture indicator has not turned green
replace the unit's filter-drier, which is probably

saturated.

Note:
Pressing
any key at this point allows the next
function to be
accessed.

To recycle the refrigerant only without pulling a
vacuum for an indefinite period of time press the
SHIFT/RESET key and the RECYCLE key on the key­

pad.
Press the SHIFT/RESET key to cancel.
For vacuum only press the SHIFT/RESET key and
the ENTER key and then press
"1".
Run the vacuum
pump as long as required and then press
"1"
or
press SHIFT/RESET to cancel.
8-48 May 1996

^?
The Aston Martin Lagonda Diagnostic System
Installation Instructions

1.
Switch off the PDU and remove all cables.

2.
Remove the cover screw (Fig 23) and remove the cover.
3. If damaged, remove the old foam gasket from the cover and replace with the new one supplied.

4.
Note the orientation of the connector. Disconnect the connector and remove the old battery pack.
5. Fit and connect the new battery pack (Fig 24) with the black cable towards the touch screen.
6. Refit the cover and cover screw.
7. Refer to the Battery Charging instructions for recharging times.
Changing the Dust Filter
The electronic module has a dust filter fitted to the underside of the module. Every three months a new filter wil
be supplied. To change the filter, proceed as follows:

1.
Switch off the mains supply and pull out the old filter (Fig 25).

2.
Feed in the new filter with the blue side facing in, pushing it well into the corners of the holder.
3. Switch on the mains supply.
Figure 25. Dust filter replacement Figure 26. Support arm adjustment
Support Arm Adjustment
Periodically the support arm mechanism may require adjustment.

1.
Remove the cross head arm fixing screw.

2.
Using a suitable screwdriver, turn the tensioning screw (Fig 26) anti-clockwise half a
turn.

3. Refit the leg fixing screw and repeat the operation on the opposite side.

4.
Check that the arm tension is enough to support the weight of the PDU without movement.
VIA Carrying Case
The VIA unit (0018) is secured into its carrying case with two fixing screws from the underside of the case. If a new
VIA is required, remove the two fixing screws and lift the VIA from the carrying case. Return only the VIA for
replacement, do not return the carrying case.
May 1996 9-23

^^?
The Aston Martin Lagonda Diagnostic System
Users Guide
Seat Belt Pretensioner Diagnostics
(where fitted)
Description
The DB7 seat belt pretensioner system operates the
drivers seat belt pretensioner in conjunction with the
Airbag system. The seat belt pretensioner control
module is located underthe right hand seat, beside the
seat control module.
The pretensioner control module calculates changes
in vehicle speed using an input signal from an
accelerometer. When a collision is detected (Rapid
reduction in vehicle speed) the pretensioner charge is
fired using electrical energy stored in a capacitor
within the pretensioner control module. Firing of the
pretensioner charge applies additional tension to the
drivers seat belt.
The airbag and seat belt pretensioner systems share the
SRS (Airbag) warning lamp. Any fault detected by the
pretensioner control module is indicated by constant
illumination ofthe
SRS
(Airbag) warning
lamp.
Flashing
of the SRS warning lamp indicates a fault in the airbag

system.

Should both systems develop faults, the pretensioner
system will permanently illuminate the warning lamp.
This would mask the airbag system warning indication.
Therefore, rectify the pretensioner fault and then retest
for faults in the airbag system
The pretensioner control module can log up to 10
diagnostic trouble codes together with a time since
each fault was alerted to the driver. Each fault will be
identified as 'Permanent' or 'Intermittent' on the PDU
diagnostic trouble codes screen.
System Connections
The Autoliv RC5 Pretensioner Control Module has an
18 pin connector featuring six shorting bridges. The
mating halves ofthe connector may be securely locked
using a double mechanical locking system.
The following pins on the control module connector
are used in the Aston Martin seat belt pretensioner

system:

Pin 1
Pin 2
Pin n
Pin 12
Pin 14
Pin 15
Case
September 1996
Ground
SRS/Airbag Warning Lamp
Drivers airbag positive
Drivers airbag negative
Serial communications
12 volt positive feed
Ground
System Fault Strategy
No single fault may cause an unexpected deployment.
The controller will supervise the airbag/pretensioner
electrical system in order to warn the driver should a
fault occur. Any fault detected by the self diagnostics
shall cause the airbag warning lamp to be activated,
and in some cases the pretensioner control module to
enter shutdown mode. In shutdown mode, the energy
ofthe reserve capacitors shall be discharged to avoid
unintended deployment.
As the ignition is switched on, the pretensioner
controller will directly discharge theenergy capacitors.
When the start up procedure is completed without
detecting any faults, the converter will be activated
allowing the capacitors to be
charged.
The system shall
be fully active within 11 seconds after switching the
ignition on providing that no faults are detected.
All system faults monitored by the controller are filtered
in software to avoid fault warnings due to transient
electrical disturbances.
If a fault which could lead to inadvertent deployment
bedetectedbythemicroprocessor,asoftwareshutdown
will be generated. However, a leakage to an earth or
positive potential in the pretensioner output circuit
shall not cause the controller to enter shutdown mode.
If
a
permanent short of the ignition transistor occurs, a
shutdown shall be generated by the hardware circuit.
If a shutdown occurs, the system shall be unable to
deploy the pretensioner after a period of
3
seconds (i.e.
capacitors discharged to under minimum deployment
voltage).
WARNING: To avoid the possibility of personal
injury caused by accidental deployment of the
pretensioner, disconnect the vehicle battery and
wait at least 10 minutes for all voltages to fully
discharge before working on the pretensioner
system. This covers the possibility of the normal
capacitor discharge circuits being inopera tive and
failing to discharge the capacitor when instructed
to do so.
If the module enters shutdown mode, all diagnostic
functions are stopped, but the communications link
remains active. A fault code corresponding to the
cause of the problem may be read by the PDU.
9-47