1997 ASTON MARTIN DB7 ESP

r^ ' ^ ^ The Aston Martin Lagonda Diagnostic System
Installation Instructions
Finishing the Test
When data analysis is finished, switch off the PDU
and disconnect it from the vehicle. Store the PDU
and cables in the carrying case and refit the case to
the base station.
Connect the PDU to the base station using cable

0064.
The base station will keep the PDU batteries
fully charged at all times (Fig 15).
Figure 15. PDU connected for recharging
Care of the Equipment
CAUTION: With the exception of those parts
referred to in the Servicing and Maintenance
section, there are no user serviceable parts. All
servicing must be carried out by GenRad Service
Centres.
Switch offthe power before cleaningtheequipment.
The Aston Martin Diagnostic System should only
be cleaned using a non-abrasive, mild cleaning
agent. Dust and other particles should be lightly
brushed from the surface before
cleaning.
Cleaning
agent should be applied to a soft lint-free cleaning
cloth and never directly to the unit. Do not soak the
cleaning cloth and take care not to allow cleaning
fluid to enter connectors.
CAUTION: Ifany liquid is spilt on theequipment,
switch off immediately.
Ensure
that the equipment

has
dried out completely before operating it again,
especially in connectors where fluid can lodge.
May 1996 9-15

The Aston Martin Lagonda Diagnostic System
Installation Instructions -=2?
Step 11
Adjust the contrast control. Is the PDU touch screen illuminated?
YES - Co to step 12
NO - Renew the PDU (0017)
Step 12
Observe the display screen. Is the screen displaying a PDU hard error symbol similar to that shown in Fig 17
YES - Note the number and refer to 'Parts Ordering'.
NO - Co to step 13
Figure 17. PDU hard error code
Step 13
Observe the screen display. Is the screen displaying the main menu (Fig 9)?
YES-Co to step 14
NO - Go to step 15
Step 14
Select the PDU system self test option and press the 'tick'
icon.
Does the screen respond?
YES - Co to step 15
NO - Renew the PDU (001 7)
Step 15
Observe the display screen. Is the screen displaying the symbol shown in Fig 18?
YES - Connection problem, go to step 17
NO - Co to step 16
Figure 18. Communications blocked
9-18 May 1996

^?
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

^^?
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

^^
The Aston Martin Lagonda Diagnostic System
Users Guide
Print Facility
The print trace and print screen facilities provided on
DB7 CD2 will enable the Dealer to print directly to a
serial printer via an isolated RS 232 cable.
General Information
This cable isdesigned to provide full electrical isolation
between the Portable Diagnostic Unit (PDU) and a
device using the RS232 serial communication port.
The cable is constructed with an in-line module that
contains the optical isolation circuitry, powered from
the PDU.
Printer type
The cable is supplied configured to suite an Epson
LX300 printer. This is the only instal lation verified and
approved by Aston Martin Lagonda Ltd.
Unexpected results may occur if used with an
unapproved printer.
Part Number Equipment type
3539-1114-03 Epson LX300 printer cable kit
comprising
3539-1169-03 Printer Cable
3539-1175-02 User Self Test Adaptor
Connecting to the PDU
Connection to the PDU RS232 port
is
made by plugging
the circular connector with the BLUE ident ring into
socket (1) on the PDU interface panel.
RS232 Protocol
The RS232 protocol operated by the PDU is 9600

baud,
8 bit, no parity,
1
stop bit,
RTS
/ CTS hardware
handshake.
Printer Configuration
When connected to the printer
a
hardcopy of the PDU
data can be produced.
25 Way Connector c rp '*= Isolator •—*«
RS232 Cable
Printer Connection
Printer
When connecting to the printer please record original
printer settings prior to making any changes. Neither
CenRad nor Aston Martin Lagonda can accept
responsibility for re-configuration of the printer for
other applications.
Self Test Adaptor
Each cable type is supplied with a User Self Test (UST)
adaptor. This allows the function of the cable to be
verified independently of a printer. Future releases of
UST software will include testing procedures for this

cable.

RS232 Printer Cable
September 1996 9-49

The Aston Martin Lagonda Diagnostic System
Users Guide [S:S3^2?
The PDU will then check the cable connections. Until all
connections are correct, the PDU will not allow progression
beyond this
screen.
Pressingthe'asterisk'icon and selecting
abort returns the operator to the general screen if an
incorrect system has been chosen.
If selection and wiring are correct a numeric keypad will
be displayed. The operator can nowenterapin numberto
be tested, using this keypad.
Pin
Numeric Keypad
Display Freezing
To assist the operator a "HOLD/UPDATE" option is
displayed on the general screen. This option is selected as
default on the general screen and allows a reading to be

'frozen'
on screen when the 'tick' icon is pressed. A 'tick'
button is also incorporated into the red probe so that a
remote 'freeze' command can be sent to PDU, holding the
reading until the operator can view the screen. A frozen
value is displayed on a 'grey' background indicating that
the value is on HOLD. Re-pressing the 'tick' icon (either
local or remote) unfreezes the display and restores the
normal display background.

b.nn

DMM
(-)
(-)
Voltage
RED PROBE
BLACK PROBE
HOLD/UPDATE
The "HOLD/UPDATE" option operates on one touch of
the 'tick' icon (or 'tick' button) irrespective of the state of
the screen backlight. Therefore it is not necessary to
reinstate the screen backlight if there has been no operator
contact with the PDU for five minutes (or longer). Pressing
"HOLD/UPDATE" reinstates the backlight and initiates/
releases display 'freeze' automatically.
System Exit
At any point during DMM operation it is possible to exit
the system by either pressing the 'asterisk' icon and
selecting abort, or pressing "EXIT" (where available)
followed by a confirming 'tick'.
The Hold/Update option
9-52 September 1996

^
The Aston Martin Lagonda Diagnostic System
Users Guide
Parameter Name
Parameters can be fault codes, inputs to, or specific
outputs from, a vehicle control module.
The number of parameters selectable is limited to 32.
If the number of parameters available for customization
exceeds the d isplay
area,
the arrow buttons wi
11
be present,
allowing display area scrolling.
The parameters declared to Datalogger are initially
presented in alphabetical order.
Record Enabled
Record enabled is used to select which signals are to be

recorded.

To select a signal for recording, touch the rectangle next
to the signal name.
The record button will then be displayed.

Nofe:
Additional rectangles may appear in other columns
beside a selected signal name, indicating that the signal
units may be changed or that the signal may be used
as
a

trigger.

It should be noted that the more parameters you select to
record the slower the PDU's sample rate will be for each
parameter e.g. The PDU may be able to monitor six
parameters sampling each parameter twice a second. If
the number of parameters is increased to twelve then the
PDU would only be able to sample each parameter once
per second, thus reducing its ability to capture fast faults;
therefore it
is
recommended that the number of parameters
is kept to a minimum.
Display Order
Parameters may be displayed on the waveform/ bargraph
screen in any order.
To set the parameter display order, press the required
rectangle to create a numbered list.
Note: It
is
not
necessary to
display all of the parameters
required to be recorded.
This has particular benefits if a parameter is to be used as
a trigger but is not required to be displayed.
Trigger Action
For a detailed description of trigger action, refer to the
Trigger Customisation description on the following page.

S.I.
Units
Certain parameters can be measured / displayed in a
number of different units eg temperature in °C or °F. If a
rectangle appears around the displayed units in the
'S.I.'

column then the units are selectable. Each time the
rectangle is pressed, the selectable units scroll one step
through the available options.
Other Features
To make parameter customization easier two icons have
been introduced on to the bottom of the screen, these are:
This icon simply puts all ofthesignals selected for
recording in alphabetical order irrespective of
the language.
A B C
This icon will put all of the signals selected for
recording at the top of the parameter list in
numerical order.

^T/^

After the parameter customization process is completed,
return to the Datalogger main menu.
Default Customisation
To cancel all customisations, press the
Customisation Reset
icon.
This will reset the
customisation on all parameters to the default

setting.

Trigger Customisation
Datalogger operates using a 'rolling memory'.
When the Record icon is selected on the waveform
display, PDU will start to record data, it will then continue
to record data until its memory is
full.

At this point it will continue recording by overriding the
oldest
data.
This process will continue indefinitely or until
the trigger is activated.
When the trigger is activated it performs a number of
functions.
a) The first function istoplaceazerotimepointwithin
the stored data, this enables the trigger point to be
easily accessible in later stages.
b) The second function is to set a timer, ensuring that
the PDU wil
I
only continue recording for the time
selected in 'test-duration'.
September 1996 9-57

The Aston Martin Lagonda Diagnostic System
Users Guide ^?
Datalogger Timing
Select the 'clock' icon from the main menu screen.
Confirm the selection using the 'tick'
icon.

The Datalogger timing screen should now be displayed.
Datalogger Timing
Signals
Sample Interval
Record time
Pre-trigger
Post-trigger
00:33:20

50%
00:16:40

50%
00:16:40
'^
23]
Datalogger Timing
The Datalogger timing screen allows customisation of the
sample interval and duration of data capture.
The display will identify the number of parameters
(channels) which have been selected to be recorded by
Datalogger.
Timing changes can only be made while data capture is
inactive. Entering Dataloggertiming while vehicle data is
being captured will display the current
settings,
but disable

selection.

Signals
The signals are the number of parameters set for sampIing
by Datalogger.
Sample Interval
The sample interval (frequency) defines the time interval
between successive block requests for all recorded
parameters.
The sample interval is selectable to enable fast response to
intermittent faults.
Note: Very short sample intervals may reduce test
duration
because ttie
PDU memory
becomes
full of
data.

Select the sample interval rectangle.
Acaiculator-style icon should nowbedisplayed. rrr?]
^
Aswellasa calculator-style icon beingdisplayed
there will bea hare
icon,
selecting this icon will
automatically set the fastest sample rate for the
selected parameters.
Note: The fastest sannple rate set using the 'hare' icon may
be too fast for some applications.
Select the calculator-style
icon.

A new screen should now be displayed.
Enter Test Duration
IDD 33 EDI
CL m m [Z]
Ci] ra [I]

1
1 2 1 3 1

0
1
Test Duration
Enter the required value in milliseconds up toa maximum
of 60,000 mS (1 min). At this stage Datalogger will not
verify if the entered sample interval can be achieved.
When Datalogger is actioned to start recording vehicle

data,
and the sample interval is shorter than the fastest
achievable capture time, a warning screen will be

displayed,
requesting changes to the sample interval.
Record Time
The record time (test duration) defines the length of the
data slice which will be preserved for analysis after the
fault occurs. The selected time will be split equally before
and after the fault trigger, e.g. a 10 minutes recording will
preserve data from 5 minutes before to 5 minutes after the
fault.
At the end of the record time the PDU will automatically
stop recording.
The record time is entered in the same way as the sample

interval,
by enabling the rectangle and selecting the
calculator-style
icon.

9-60 September 1996