1997 ASTON MARTIN DB7 warning light

Electrics
Airbag System [n:M^^^?
Airbag DM Fault Code 99
Rapid continuous flashing of the airbag warning
light - Both front crash sensors disconnected.
Normal Operation
Each crash sensor has three wires. Two deploy the
airbag and monitor the sensors connection to the
diagnostic monitor. The third wire monitors the
mounting of the sensor to the vehicle bodywork. A
code99isdeclaredifbothsensorsaredisconnected
and not properly grounded.
Fault Analysis
Disarm the airbag system and fit airbag simulators
(6.4.21.4).
Check continuity of all circuits listed below and
service as necessary.
LH Crash Sensor
DM Pin
1-6
1-12
2-9
RH Crash Sensor
DM Pin
1-2
1-11
2-8
Sensor Pin
1
2
4
Sensor Pin
1
2
4
Also check for correct grounding of the diagnostic
module and the sensor cases.
Reconnect all connectors, clear fault code 99.
Switch off the ignition and then switch on again.
Check that the airbag warning lamp comes on at
'ignition on' and extinguishes after approximately
six seconds on satisfactory completion of the airbag
system self-check.
Rearm the airbags (6.4.21.4).
6-100 September 1996

Electrics //—>> ^^^^^^ • >^
Seat Belt Pretensioner I'•—
-"i-t.
^-^
JH—X

System Fault Strategy
No single fault may cause an unexpected deployment. The controller will supervise the pretensioner electrical
system in order to warn the driver should a fault occur. Any fault detected by the self diagnostics shall cause the SRS/
airbag warning lamp to be activated, and in some cases the pretensioner control module to enter shutdown mode.
In shutdown mode, the energy of the reserve capacitors shall be discharged to avoid unintended deployment.
As the ignition is switched on, the pretensioner controller will directly discharge the energy capacitors. When the
start up procedure is completed without detecting any faults, the DC/DC converter will be activated allowing the
capacitors to be charged. The system shall be fully active within
11
secondsafterswitchingthe 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 is detected by the microprocessor, a software shutdown 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 inoperative
and failing to discharge the capacitor when instructed to do so.
WA RNING: Do not make any electrical measurements on the pretensioner squib. Electrical measurement devices
can induce sufficient voltage to cause unintentional firing of the pretensioner assembly
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.
Assembly/Removal/Service I nstructions
WARNING: In the event of a vehicle impact where the airbags and the seatbelt pretensioner (if fitted) are
deployed, the following actions MUST be performed:
Check the condition of the
seatbelts,
steering wheel, steering column, all connections to airbags, and the column
switchgear connectors for integrity and damage. If in any doubt, replace suspected parts for new parts.
Replace both crash
sensors,
the safing sensor and the seatbelt pretensioner module (if fitted).
On completion of all repair procedures, switch on the ignition and check that the Airbag/SRS warning light
comes

on when the ignition is switched on and extinguishes after approximately six seconds indicating satisfactory
completion of the airbag and pretensioner
system
self
tests.

Vehicles for the North American, Australian and Japanese markets are fitted with drivers seat belt pretensioner
systems and are fitted with a shorting plug in the yellow connector adjacent to the pretensioner control module.
Vehicles for other markets do not have drivers seat belt pretensioners fitted but have a blanking plug in the yellow
connector adjacent to the pretensioner control module.
6-102 September 1996

The Aston Martin Lagonda Diagnostic System
Installation Instructions E:MB^^?
Introduction The Aston Martin Diagnostic System
This guide contains instructions for the installation
of the Portable Diagnostic Unit hardware in Aston
Martin Dealer workshops. To achieve maxinnum
benefit from the system, please follow the
instructions carefully. The following System
Diagram shows the principal system components
and panel details.
This introduction briefly describes the system and
its capabilities. This is followed by the Installation
and Power-Up procedures which give detailed
instruaions on how to start the system and access
the self-contained Interactive
Training
Programme.
The subsequent sections detail the fault diagnosis
and maintenance procedures.
WARNING:
The equipment must
only
be used by

trained
personnel.
Care should
be taken to use the

equipment in accordance with the operating

procedures.
Observe
all safety
warnings
in this

guide.
If any part of
the system is damaged do not

use it. Call your local CenRad
Service
Centre

immediately
for a
substitute
part.
Refer to
'Parts

Ordering'.
The Aston Martin Diagnostic System is a new
generation diagnostic
tool
which fulfils
a
number of
functions in aiding the technician to quickly and
accurately locate faults. The heart of the system is
the Portable Diagnostic
Unit,
a
lightweight powerful
computer/measurement system providing a step-
by-step user friendly interface for the technician.
PDU functions include:
Data Logger - The ability to monitor and record
control module signals even whilst the vehicle is
being driven.
On-Line Help-Containing detailed descriptions in
the
operation
ofthevehicleselectroniccomponents.
Vehicle Setup - The ability to setup various
adjustable parameters to their optimum settings.
Diagnostic Trouble Codes - The ability to extract
recorded fault information from the DB7's control
modules.
Each of
these
funaions is described in detail in the
PDU Users Guide.
WARNING: If
the system is used to measure high

voltages,
these voltages can appear on the pins of

other
connectors in
the
system.
Ensure
that socket
covers
are
fitted
on
unused
sockets.
Ensure
that all

connections
are
made
prior to
applying the high
voltage to
the
probes.
Do not
leave the equipment
unattended
in
this
state.
The maximum
voltage

that may be applied
between the
test
probes is 150
volts
AC or DC.
Radio Interference Statements
This digital apparatus does not exceed the Class A
limits for radio noiseemissionsfromdigital apparatus

as set
out
in
the radio interference regulations of the
Canadian Department of Communications.
This equipment has been tested and found to
comply with the limits for Class A digital device
pursuant to part 15 of the Federal Communications
Commission (FCC) rules. However, operation in
close proximity to domestic communication
equipment may cause interference. It is the
responsibility of the user to avoid or correct this

condition.

9-2 May 1996

^^?
The Aston Martin Lagonda Diagnostic System
I nstal lation I nstructions
Bench Mounting
The base station may also be mounted on a bench, which
must be in a safe position, stable and protected form
hazards and impacts. The base station must be mounted
at the back of the bench. 'Z' clips are provided for
permanent mounting. The bench surface must be kept free
from dust at all times.

CAUTION:
A gap under the base station must be
maintained free from obstructions to allow a flow of air
under the unit for cooling.
Electronic Module installation
WARNING: The base station electronic module must be
disconnected from the mains supply prior to installation/
removal from the base station assembly. DO NOT
reconnect to the mains supply until the module is safely
fitted into the base station. This unit must be earthed.

Note:
Users in North America are advised to replace the
ceramic mains fuse in the electronic module with theglass
fuse supplied.
Procedure

1.
Unlock the base station door

2.
Pull the right spring-loaded hinge (Fig 4-1) and
remove the door.
3. Removetheelectronicsmodulefrom the packaging
and place it on a firm surface.

4.
Remove the two screws and washers from the front
of the module (Fig 4-3).
5. Insert the mains power lead into the socket at the
rear of the module Fig 4-4), DO NOT CONNECT
TO THE MAINS SUPPLY.
6. Insert the two guide pins on the sides of the module
(Fig 4-5) into the base station slots.
7. Slide the module into the base station until fully

home,
raise the front so that it is level and draw it
slightly forward.
8. The two connectors on the front of the module will
appear through the matching holes in the base

station.
Support the module whilst refitting the two
retaining screws and washers (Fig 4-6).
9. Secure the mains lead to the underside of the base
station using the two cable ties provided (Fig 4-7).

10.
If bench mounting, the base station will need to be
turned on its back to install and secure the mains

lead.

11.
Refit the base station door.
CAUTION: Take care to avoid the sharp edges of the
module whilst installing. Take care to support the
module from the underside until the mounting
screws are secured.
Figure 4. Electronic Module Installation
May 1996 9-9

^27
The Aston Martin Lagonda Diagnostic System
Users Guide
Engine Diagnostics - 97 MY
Selecting Engine Diagnostics from the Vehicle Area screen
brings up the following Engine Diagnostics Screen.
Engine Diagnostic
• Diagnostic Trouble Codes
• KOEO on Demand Self Test
• KOER on Demand Self Test
• OBDII Readiness Tests
• Output State Control
• Throttle Checks
• Exit
o
Diagnostic Trouble Codes (DTCs)
On selecting DiagnosticTrouble
Codes,
the PCM memory
will be scanned and any recorded DTCs will be decoded
and displayed.
The engine and transmission DTCs are integral to the On
Board Diagnostics (OBDII) system and are ful ly described
in the DB7 OBD II Diagnostics Manual.
Before attempting to clear the logged DTCs, record all
logged DTCs for use in subsequent fault analysis.
All logged DTCs may be cleared by selecting the EEC-V
EMS DTCs
title.
This will bring up the Clear
(C)
icon which
may be selected and confirmed to clear all logged DTCs.
Note that on clearing all logged DTCs you will also clear
the associated timers, counters and fault history files (and
extinguish the engine management warning lightfor North
American vehicles). The OBD II readines test status will
also clear down and a PI 000 (OBD II readiness test
incomplete) trouble code will be set.. A full drive cycle
(see DB7 OBD II Diagnostics Manual) must be completed
to clear the PI 000 code if required. The PI 000 code will
clear automatically after some miles of driving when all
required tests have satisfactorily completed.
Caution: If a transmission code is logged in the PCM, the
TCM DTCs must be cleared first and then clear the PCM
DTCs. If the PCM DTCs are cleared without clearing the
TCM, the TCM code will immediately reset in the PCM
when power is restored.
Key On Engine Off (KOEO) and Key On Engine
Running (KOER) On Demand Self Tests
Before either the KOEO or KOER test will run, the engine
coolant temperature must be in excess of
BO'C.
Select and
confirm either the KOEO or KOER test. If the coolant
temperature is too low, the Pre Test Engine Warm Up
screen will appear. Start the engine and run until coolant
temperature is at 80+°C.
Pre Test Engine Warm Up
Value : 41°C
80 Engine Coolant Temperature {°C)
Waiting for engine to reach
normal operating temperature
o
KOEO Test
As coolant temperature rises through the BO'C level, the
technician will be requested to turn the ignition off and
then on again. The KOEO test will then commence. Static
inputs to the PCM will be checked and any faults detected
will be recorded and displayed as DTCs. If any DTCs other
than PI 000 are logged, go to the OBD II Diagnostics
Manual and resolve the concern(s) using the OBD 11
diagnostic procedures.
KOER Test
If coolant temperature level is below 80°C, the technician
will be prompted to start and run the engine until coolant
temperature rises above 80°C. As the temperature passes
the 80°C
level,
the KOERtest will commence automatically.
If coolant temperature is above the 80°C level, the
technician wi
11
be requested to start the engine. The KOER
test will commence as the engine is started. Dynamic
inputs to the PCM will be checked and any faults detected
will be recorded and displayed as DTCs. If any DTCs other
than PI 000 are logged, go to the OBD 11 Diagnostics
Manual and resolve the problem(s) using the OBD II
diagnostic procedures.
September 1996 9-33

^7
The Aston Martin Lagonda Diagnostic System
Users Guide
Diagnostic Trouble Codes
Introduction
The 'Diagnostic trouble codes' application enables the
PDU to monitor the trouble codes logged in selected
control module's and provides the following functions:
• Decode and display any trouble codes logged by
the control module(s) being monitored.
• Decode and display enhanced diagnostic
information, together with any count of the number
of occurrences, when supported by the control
module(s).
• Clearsomeorallofallthesetroublecodes selected
by the user on the PDU screen, when supported by
the control module(s).
Diagnostic Trouble Codes are logged by the Engine
Management and by the Automatic Transmission control
units and can be accessed using the PDU. Logged codes
in the 95 MY Teves Mk II ABS controller can only be
accessed using the brake warning light. The Air
Conditioning control unit does not log trouble codes.
Operation
From the Main Menu make the following selections:
Select Diagnostics
Select Engine or Transmission
The system will then load the appropriate
software
Select Diagnostic Trouble Codes
Connect the PDU to the car as shown on the
screen diagram
Select the / icon to confirm connection
The PDU will then interrogate the chosen control
unit and will display any logged trouble codes.
If no trouble codes have been flagged by the control
module, the PDU will display a screen similar to Fig. 15
The trouble code screen will be headed by a module title
block followed by a list showing all logged trouble codes
for the seleaed module.
Note: There may be more logged diagnostic trouble
codes than displayed on the first
screen.
Use the 'up
arrow' and 'down arrow' icons if
necessary
to scroll
through the total display.
On the Zytek engine management system only, each
trouble code definition will be individually selectable to
invoke the clear trouble codes screen. If one or more
trouble codes are selected, the clear all and clear selected
trouble code icons will be displayed.
On all other systems, only the 'Clear All' function is
available.
'Clear All' and 'Clear Selected Codes' Icons
Freeze Frame Data
m*
As any engine management trouble code is

logged,
the system takes a snapshot (freeze
frame) and records the state of all signals at
that time.
On the Zytek engine management system (95 MY), freeze
frame data can be displayed by selecting a logged trouble
code and touching the 'snowflake'
icon.

On the 97 MY EEC V engine management system, freeze
frame data is accessed using the OBD II scan
tool.

ECC-V EMS DTC'S
No fault codes present
l^
D
a
El
The No Fault Codes screen
September 1996 9-53

The Aston Martin Lagonda Diagnostic System
Users Guide
•=2?

Clear all Trouble Codes
Selecting the clear all trouble codes icon will invoke a
confirmation window.
EEC-V EMS
dri
dri
CONFIRM
Clear all logged trouble
codes?
O

'Clear
All Codes' confirmation
screen

Selectingthe'tick'will instructthePDU to clear all logged
trouble codes in the selected module
and
return to the no
logged codes screen.
Select the 'tick' icon to exit Diagnostic Trouble Codes.
Clear Selected Trouble Codes
(95 MY Zytek Engine Management Only))
If
you
wish only to clear selected codes on the Zytek ECU
and
leave others
for later
investigation,
proceed
as
follows:
Highlight only the trouble code(s) to be cleared.
ZYTEK EMS
1 : Idle speed control valve driver #1
5 : Purge Valve driver #1
12 : Cooling fan#l relay driver
14 : Lannda heater
#2
driver
1 : Idle speed control valve driver #1
Highlighting
Selected
Trouble
Codes

Select the 'clear selected trouble codes'
icon;
this will
invoke a confirmation window.
Selectingthe 'tick' icon will instruct
the
PDU to clear only
the selected trouble codes from the control module fault

table,
and if successful, the system will return to the
'Diagnostic trouble codes' screen.
If any attempt to clear trouble codes is unsuccessful, a
warning window will be displayed.
This will indicatethat
some selected
trouble codes remain
logged,selectingthe'tick'iconwillreturntothe'Diagnostic
trouble codes' screen.
Select the 'tick' icon again to exit Diagnostic Trouble
Codes.
9-54 September 1996

The Aston Martin Lagonda Diagnostic System
Users Guide 5^^?
Only the data within the selected time period will be

stored.
A trigger is used to define the zero time point on
any waveform display. This is used to make it easier to
locate the actual point at which the fault occurred on the
waveform display. Triggers may take three forms.

1.
Manual Trigger
A manual trigger would be used in circumstances where
the technician can clearly identify the point when the fault
occurs and has access to the PDU at this point.
The trigger icon should be pressed on the waveform /
bargraph display (ortheon-road trigger icon) at the instant
the fault occurs. This will then become the zero point for
the waveform/bargraph display. The waveform/bargraph
display up to this point would have a negative form.

2.
Fault Code Trigger
The fault code trigger is used when the first indication of
a fault is normally by the appearance of a warning lamp
within the instrument pack. For some vehicle systems
Datalogger can trigger on specific fault codes, this type of
triggering is more precise than simply triggering on the
warning lamp.
This trigger
is
selected during the parameter customisation
process. To select a fault code to trigger 'on', set the fault
code (parameter) to record.
Asign the display order by touching the rectangle below
the Eye icon repeatedly until the desired display order
number is shown.
Press the rectangle in the trigger column.
Highlight the fault code parameter again and select the
magnifying glass
icon.
The trigger customisation screen
will be displayed.
Select the appropriate trigger style icon and select the tick
icon to confirm.
Press the Tick icon again to return to the main Datalogger

screen.

Select the Record icon to start data capture.
The unit will trigger when the fault code appears and will
set the zero time point of the waveform / bargraph display.
3. Specific Signal Trigger
It is possible to select a specific parameter or signal to
trigger Datalogger.
Triggering on specific signals is likely to be used when the
vehicle system has no on-board diagnostics or when
diagnostic information is not readily available at the time
the fault occurs, e.g. air-conditioning.
Thistypeoftriggershouldonly be used when it is known
that a particular signal has certain characteristics at the
time the fault occurs, e.g. one signal will always go from
12 Volts to ground, bringing on a warning lamp when a
particular fault occurs,
as
this is a known event, this signal
may be used to trigger the PDU.
Trigger Selection
Any of the record enabled parameters may be used to
trigger Datalogger.
To select a trigger highlight the parameter name, a
magnifying glass type icon will appear at the bottom of the

screen.

Select the magnifying glass type
icon.

The trigger action screen should be displayed.
ABSWl
Trigger

-T-

Anti-lock Brak
^ J^HL
^M

ov

es Warning
L

zF
!
=^

S.I.

°C
Ei
.amp
i
m,
Trigger Action Screen
9-58 September 1996