1997 ASTON MARTIN DB7 brake fluid

Introduction
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Safety Precautions L —^ ^^—^
Safety Precautions "
All service workshops are a source of potential danger and repair work should only be performed by technically
trained staff following the procedures in this manual. A safety conscious approach to the performance of all service
procedures must be observed at all times. Statutory requirements governing all aspects of health and safety at work
including directives for the proper use of materials and equipment must be implemented.
The following contains a list of particular safety precautions which should be observed; it is not intended to be
exhaustive.
Air Conditioning System
Do not disconnect any air conditioning refrigerant system pipes unless trained and instructed to do
so.
The refrigerant
used can cause blindness if allowed to contact your eyes.
Chemical Handling and Storage
Chemicalsusedintheservicingofmotorvehiclesincludeacids,adhesives, antifreeze, brake fluids, coolants, grease,

oil,
paint, resin and solvents. Exposure to certain chemicals through direct contact or inhalation can be
fatal.

Potential hazards may also be present through the incorrect use, storage and handling of chemicals causing a fire
risk. The following precautions should be observed.

1.
Strictly adhere to handling and safety information found on containers and labels.

2.
Do not store chemicals in unlabelled or incorrectly labelled containers.
3. Containers used for storing chemicals should not be left
open;
there is a risk of
spilling,
or evaporation of fumes
which may be inflammable or toxic.

4.
Do not mix chemicals unless instructed to do so following manufacturers guidelines.
5. Do not inhale chemical materials to determine identity, they may be toxic.
6. Do not use petrol, kerosene, diesel
fuel,
gas oil, thinners or solvents for washing
skin.

7. Containers whose capacity is over 25 litres (5 gallons) require a bund wall in order to contain spillages.
8. Chemicals based on solvents such as paint should not be sprayed in a confined space; work areas used for
such operations should be well ventilated and fume extraction equipment should be utilised.
9. Ensure that adequate ventilation is provided when volatile de-greasing agents are being used.
WARNING: Fume extraction equipment must be in operation when
solvents
are
used
e.g.
trichloroethane, white
spirit, SBP3, methylene chloride, perchlorethylene.
WARNING: Do not smoke in the vicinity of volatile de-greasing agents.

10.
Avoid splashing the
skin,
eyes and clothing.

11.
Clean chemicals from the skin and clothing as soon as possible after soiling.

12.
Wear protective clothing such as goggles, non porous gloves and apron when hand
I
ing battery acid and other
corrosive and toxic substances.
iv April 1997

^7
Electrics
Component Index Sheet 1-97 MY
Component
Name
ABS ECU
ABS Wheel Speed Sensor - Front RH
ABS Wheel Speed Sensor - Front LH
ABS Wheel Speed Sensor - Rear RH
ABS Wheel Speed Sensor - Rear LH
Airbag Crash Sensor RH
Airbag Crash Sensor LH
Airbag Diagnostic Monitor
Airbag (Drivers)
Airbag (Passengers)
Airbag Safing Sensor LHD
Air Conditioning Compressor Clutch
Air Conditioning Control
Air Conditioning Trinary Switch
Air Conditioning Unit
Air Pump
Air Temperature Sensor (IAT1)
Air Temperature Sensor (IAT2)
Alarm LED Inverter
Alarm Sounder
Alternator (Generator)
Ambient Temperature Sensor
Barometric Pressure Sensor
Blower Fan LH
Blower Fan RH
Bonnet Switch
Boot Lamp LH
Boot Lamp RH
Boot Lock Actuator
Brake Fluid Level Sensor
Camshaft Sensor (CMP)
Capacitor (Generator)
Catalyst Overtemperature/Speed Warning Module
CD Autochanger
Central Locking Unit '
Cigar Lighter
Column Switchgear Assembly
Coolant Low Level Sensor
Coolant Temperature Sensor (ECT)
Coolant Temperature Sensor - Temp Gauge
Courtesy Light
Crankshaft Position Sensor (CKP)
Cruise Control Clutch Switch (RHD)
Cruise Control Disable and Stop Lamp Switch
Cruise Control On/Off Switch
Cruise Control Servo Unit
Cruise Control Set Switch
Diagnostic Socket - Lower
Diagnostic Socket - Upper
Door Closed Microswitch (Drivers)
Door Closed Microswitch (Passengers)
Door Lock Motor (Drivers)
Door Lock Motor (Passengers)
Door Lock Switch (Drivers)
Component
Location
(Figure No.-ltem No.)
1-5
1-3
1-3
8-1
8-1
2-3
2-3
4-2
9-6
9-1
2-6
9-4
9-2
9-5
9-2
9-3
3-7
3-11
7-8
2-4
3-12
1-1
8-6
10-10
10-4
2-2
10-8
10-6
10-7
16-3
3-2
1-2
4-8
5-5
6-10
6-5
10-5
10-3
3-4
3-3
10-9
3-1
10-2
1-4
6-6
2-8
6-7
11-3
11-3
7-6
7-6
11-6
11-9
11-5
Circuit
Reference
(Sheet No.-Coordinates)
20-A1
20-D2
20-D3
20-B6
20-C6
3-D1
1-C3
11-C6
9-A3
11-C4
12-B4
3-C1
3-D3
3-D1
11-CI
1-C2
5-C1
5-B3
14-B6
1-B2
5-A6
1-A2
4-A4
8-A3
12-C3
1-C5
15-A4
16-D3
16-C6
20-B3
5-C1
5-A5
11-C3 Japan Only
10-B3 Rear of Radio
12-D4
13-A3
9-A2
3-A3
5-B1
5-C1
9-B1
5-A2
3-C5
9-A3
13-A5
2-A6
13-B5
10-A6
10-A5
21-A2
22-A2
21-B1
22-Bl
21-A2
September 1996 6-43

5^^
Body and Trim
Roof Control System
Roof Control System
LH Roof
Ram
n
Roof Down Roof Down
n
RH Roof
Ram
Roof
Motor
Roof Up
Fluid
Reservoir I
Roof Up
Roof Up
Relay
LH Window
Up Relay
LH Window
Motor LH Window
Down Relay
Roof Down Switch
-o o-
Roof Down
Relay
RH Window
Up Relay
Right
Quarter
Light
RH Window
Down Relay
RH Window
Motor
Gearbox Switch
o~o
o o-Handbrake Switch (Man)
Park + Handbrake (Auto)
Figure 2. Roof System - Control Schematic Diagram
May 1996 7-9

^^?
The Aston Martin Lagonda Diagnostic System
Users Guide
Transmission Diagnostics
Selecting 'Transmission from the vehicle area menu will
present the technician with the following transmission
diagnostic tools menu:
Transmission Diagnostic
• Datalogger
• Diagnostic Trouble Codes
o
The Datalogger function is fully described in the worked
example at the rear of this PDU Users Guide.
Transmission Datalogger
The PDU datalogger function may be used to monitor the
following transmission controller signals
DIGS Number of DTCs Logged
The Diagnostics status manager (DSM) receives and
processes fault information and decides when a DTC
should be logged and the MIL turned on (if enabled). The
actual total stored is indicated by the parameter DTCS.
FBRAKE Brake Switch
The footbrake switch signal is input to the
TCM.
The input
is normally at ground potential and goes open circuit
when the brakes are applied. If the torque converter
clutch is applied it will disengage when this signal is

detected.

FMA Actual Force Motor Current
The force motor regulates the transmission fluid pressure.
It is a variable force solenoid whose coil current is
determined by the TCM. Range 0 -1.245 amps. A driver
circuit limits excessive current flow and performs a
ratiometric comparison of Desired (commanded) Force
Motor Current and Actual Force Motor current. The
parameter monitors the Actual Force Motor current 1 Bit
= l/204.8amps.
HOT Hot Mode
The signal from the transmission temperature sensor is
used to control TCC and line pressure. It is also used in
many diagnostic signals and is a critical component for
OBD II. Above 120°C the TCC is on in 2nd, 3rd and 4th

gears.
This reduces transmission temperature by decreasing
the heat generated by the torque converter. It also
provides maximum cooling by routing transmission fluid
directly to the transmission cooler in the radiator. When
the Hot Mode is ON the bit is set to 1.
IGN+ Ignition Feed Positive
The TCM receives ignition voltage through TCM pin 53.
MD Desired Force Motor Current
The force motor regulates the transmission fluid pressure.
It is a variable force solenoid whose coil current is
determined by the TCM. Range 0 -1.245 amps. A driver
circuit limits excessive current flow and performs a
ratiometric comparison of Desired (commanded) Force
Motor Current. The parameter mon itors the Desired Force
Motor current 1 Bit = 1/204.8amps.
RATIO Actual Gear Ratio
The diagnostic detects malfunction in the transmission
output components by monitoring the actual gear ratio.
The actual gear ratio is calculated using input (Ni) and
output speed (No): Ratio = Ni/No. This is compared with
the standard gear ratio for each gear. Malfunction can be
defined as: actual gear ratio is not equal to any of the
standard gear ratios.
RPM Engine Speed
The engine speed signal is input from the instrument pack.
The
signal
origi
nates
at the crankshaft
sensor.
The crankshaft
sensor signal is modified by the PCM and the instrument
pack before being input to the TCM.
SSA Shift Solenoid A
Shift solenoid A is attached to the valve body and its outlet
is open to exhaust when it is switched off. A OFF - outlet
open - 2nd and 3rd gears selected. The solenoid is
energised by the TCM providing an internal ground to
close the outlet. A ON - outlet closed -1 st and 4th gears

selected.

SSB Shift Solenoid B
Shift solenoid B is attached to the valve body and its outlet
is open to exhaust when it is switched off. B OFF - outlet
open - 1st and 2nd gears selected. The solenoid is
energised by the TCM providing an internal ground to
close the outlet. B ON - outlet closed - 3rd and 4th gears

selected.

September 1996 9-41

^?
The Aston Martin Lagonda Diagnostic System
Users Guide
Climate Control Diagnostics
The air conditioning control module is located at the right
end of the air conditioning unit. Since this controller uses
a unique communications protocol, the PDU must be
connected directly to the unit via the Vehicle Inerface
Adaptor as shown in the following cable setup screen.
Cable Setup
Adigitalmicroprocessorwithin the control module receives
data signals from the operator controlled switches.
Comparison of these signals with those returned from
system temperature sensors and feedback devices results
in the appropriate output voltage changes needed to vary:
Blower motor speed, flap position and the solenoids
which respond to operator selected temperature demand.
The air from two blower motors is passed through the
evaporator matrix which, depending on the positions of
the humidity buttons, removes heat from the incoming air.
Dependingon the position of the two blend flaps, the cold
air either passes directly to the vehicle outlet vents, or is
passed through the heater matrix to be reheated and then
to the vehicle outlet vents.
The amount of air passing through the heater matrix is
infinitely variable depending on ambienttemperature and
the temperature selected within the vehicle.
Selecting 'Climate Control' from the vehicle area menu,
will presentthetechnician with the dataloggertool selection

screen.

Details of the signals which may be monitored in the
system may be found in the DB7 Workshop Manual -
Section 8 - Air Conditioning'
Anti-Lock Braking Diagnostics
The Teves Mk IV Braking System consists of two sub­
systems, power braking and anti-lock braking.
The PDU software(DataLogger) only allows the monitoring
of the anti-lock braking system.
The ABS System consists of:
Four wheel speed sensors.
One control module.
Seven solenoid valves.
One pressure switch.
One fluid level switch.
The ABS System
is
controlled and continuously monitored
by the ABS control module, which automatically
switchesoffthesystemifafailure is identified, illuminating
a warning lamp and leaving
full,
boosted braking to all
wheels. A wheel speed sensor is installed at each wheel.
Their wheel speed related signals are processed by the
control module, which triggers the solenoid valves to
modulate hydraulic pressure, preventing the wheels from

locking.
The control module also monitors the fluid
level and will inhibit ABS operation should lowfluid level
be detected.
The Datalogger function will permit monitoring of the
complete system apart from the solenoid valves. The
control module transmits short duration test pulses of 25
to 100 microseconds to the solenoid valves. These
pulses are too fast for the PDU to monitor and as a result
would cause confusing waveforms.
Selecting 'Anti-Lock Braking' from the vehicle area menu,
will present the technician with the following menu of
diagnostic tools screen:
Anti-Lock Brakes Diagnostic
Datalogger
Diagnostic Trouble Codes
o
ABS Diagnostic Trouble Codes
The DTCs which are supported in the Teves Mk IV ABS
system are listed in the workshop manual - Section 5
Brakes Wheels and Tyres.
September 1996 9-43