Engine Diagnostics - 97 My; Diagnostic Trouble Codes (Dtcs); Koeo Test; Koer Test - Aston Martin DB7 Workshop Manual

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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 O B D 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 O B D 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 O n Engine O f f (KOEO) and Key O n Engine
Running (KOER) O n D e m a n d 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
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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
w i l l be recorded and displayed as DTCs. If any DTCs other
than PI 000 are logged, go to the O B D II Diagnostics
Manual and resolve the concern(s) using the O B D 1 1
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 1 1 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 O B D 1 1 Diagnostics
Manual and resolve the problem(s) using the O B D II
diagnostic procedures.
September 1996 9-33