2010 ASTON MARTIN V8 VANTAGE Workshop Manual

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
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Typical HO2S response rate entry conditions : Minimum Maximum
Short Term Fuel Trim Range 90% 110%
Engine Coolant Temp 150 oF 240 oF
Intake Air Temp 140 oF
Engine Load 20% 50%
Vehicle Speed 37 mph 55 mph
Engine RPM 1500 rpm 3000 rpm
Time since entering closed loop fuel 10 seconds

Typical HO2S response rate malfunction thresholds:
Voltage amplitude: < 0.4 volts

HO2S response rate temporary disablement conditions ( other than entry requirements ) :
Disabled if a lack of switching fault is present, also sensors noted in “Sensors OK” section.


Rear HO2S Signal.

A functional test of the rear HO2S sensors is done dur ing normal vehicle operation. The peak rich and lean
voltages are continuously monitored. Voltages that exceed the calibratable rich and lean thresholds
indicate a functional sensor. If the voltages have not ex ceeded the thresholds after a long period of vehicle
operation, the air/fuel ratio may be forced rich or lean in an attempt to get the rear sensor to switch. This
situation normally occurs only with a green catalyst (< 500 miles). If the sensor does not exceed the rich
and lean peak thresholds, a malfunction is indicated.

Rear HO2S Check Operation:
DTCs Bank 1 - P0136, Bank 2 - P0156
Monitor execution once per driving cycle
Monitor Sequence after 'Upstream Response' test
Monitoring Duration 20sec for excursion

Typical Rear HO2S check entry conditions : Minimum Maximum
Inferred exhaust temperature range 400 oF 1600 oF
Rear HO2S heater-on time 120 seconds
Throttle position part throttle
Engine RPM (forced excursion only) 1000 rpm none

Typical Rear HO2S check malfunction thresholds:
Does not exceed rich and lean threshold envelope: Rich < 0.25 volts
Lean > 0.65 volts

Rear HO2S temporary disablement conditions (other than entry requirements) :
None.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
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HO2S Heaters, front and rear.

The HO2S heaters are monitored for circuit continuity. A HO2S heater fault is determined by turning the
heater on and off and looking for corresponding voltage or current change in the heater output driver
circuit in the PCM.

HO2S Heater Monitor Operation:
DTCs Bank 1 - P0135 Front, P0141 Rear
Bank 2 - P0155 Front, P0161 Rear
Monitor execution Change of Heater state (at least once per drive cycle).
Monitor Sequence none
Monitoring Duration < 5 seconds

Typical HO2S heater check malfunction thresholds:
Indicated voltage or current does not match commanded state.

HO2S heater temporary disablement conditions (other than entry requirements) :
None.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
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Differential Pressure Feedback EGR System Monitor

Where a vacuum driven EGR valve is used on the base application, the EGR System Monitor will consist
of a series of electrical and functional tests for the various aspects of system operation. First, the
Differential Pressure Feedback EGR (DPFE) sensor input circuit is checked for out of range values (P1400
P1401). The Electronic Vacuum Regulator (EVR) output circuit is checked for opens and shorts (P1409).


EGR Electrical Check Operation:
DTCs P1400, P1401, P1409
Monitor execution continuous, during EGR monitor
Monitor Sequence none
Monitoring Duration 4 seconds to register a malfunction

Typical EGR electrical check entry conditions:
EGR system enabled

Typical EGR electrical check malfunction thresholds:
DPFE sensor outside voltage: > 4.96 volts, < 0.195 volts
EVR solenoid smart driver status indicates open/short



The differential pressure indicated by the DPFE sensor is also checked at idle with zero requested EGR
flow to perform the high flow check. If the differen tial pressure exceeds a calibratable limit, it indicates a
stuck open EGR valve or debris temporar ily lodged under the EGR valve seat (P0402).

EGR Stuck open Check Operation:
DTCs P0402
Monitor execution once per driving cycle
Monitor Sequence Done after P1400 and P1401 tests
Sensors OK CPS, ECT, IAT, MAF, MAP, TP
Monitoring Duration 10 seconds to register a malfunction

Typical EGR stuck open check entry conditions : Minimum Maximum
EVR Duty Cycle (EGR commanded off) 0% 0%
Engine RPM (after EGR enabled) at idle at idle

Typical EGR stuck open check malfunction thresholds:
DPFE sensor voltage at idle versus engine-off signal: > 0.6 volts

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
[email protected] AML EOBD Monitors 07 ROC.doc Page 14 of 43
After the vehicle is started, during vehicle acceleration, the differential pressure indicated by the DPFE
sensor at zero EGR flow is checked to ensure that both hoses to the DPFE sensor are connected. Under
this condition, the differential pressure should be zer o. If the differential pressure indicated by the DPFE
sensor exceeds a maximum threshold or falls below a minimum threshold, an upstream or downstream
DPFE hose malfunction is indicated (P1405 P1406).

EGR Hose Check Operation:
DTCs P1405, P1406
Monitor execution once per driving cycle
Monitor Sequence Done after P0402 test
Sensors OK MAF, MAP
Monitoring Duration 2 seconds to register a malfunction

Typical EGR hose check entry conditions : Minimum Maximum
EVR duty Cycle (EGR commanded off) 0% 0%
Mass Air Flow 8 lb/min
Inferred exhaust back pressure 13 in H2O

Typical EGR hose check malfunction thresholds:
DPFE sensor voltage: < -7 in H2O, > 7 in H2O


After the vehicle has warmed up and normal EGR rates are being commanded by the PCM, the low flow
check is performed. Since the EGR system is a closed loop system, the EGR system will deliver the
requested EGR flow as long as it has the capacity to do so. If the EVR duty cycle is very high (greater
than 80% duty cycle), the differential pressure indicated by the DPFE sensor is evaluated to determine the
amount of EGR system restriction. If the differential pr essure is below a calibratable threshold, a low flow
malfunction in indicated (P0401).

EGR Flow Check Operation:
DTCs P0401
Monitor execution once per driving cycle
Monitor Sequence Done after P1405 and P1406 tests
Sensors OK CPS, ECT, IAT, MAF, MAP, TP
Monitoring Duration minimum 70 seconds to register a malfunction

Typical EGR flow check entry conditions: Minimum Maximum
EVR Duty Cycle 80% 100%
Engine RPM 2500 rpm
Mass Air Flow Rate of Change 6% prog. loop
Inferred manifold vacuum 6 in Hg 10 in Hg

Typical EGR flow check malfunction thresholds:
DPFE sensor voltage: < 6 in H2O

EGR Monitor temporary disablement conditions ( other than entry requirements ) :
Non-operational when base feature disabled, including matching base feature temperature disablement.
Low Barometric Pressure Conditions.
Reporting of faults suppressed below 32° F to prevent mis-diagnosis due to ice. Monitor is still operational
and continues to check, reporting any faults when temperature > 32 °F.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
[email protected] AML EOBD Monitors 07 ROC.doc Page 15 of 43
If the above temporary disablement conditions (inferred ambient temperature and low barometric
pressure) are encountered, the flow test will be su spended and a timer will accumulate. Whenever the
temporary disablement conditions are no longer present the timer will decrement, and the flow test will
operate as normal. However, in extended temporar y disablement conditions if the timer reaches a
calibrated threshold (typically 800 seconds), the EGR flow test is disabled for the remainder of the current
drive cycle, and the EGR monitor I/M readiness bit will be set.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
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Electronic Throttle Monitor

Where ETC is used, the system monitor incorporates a complex safety strategy. The main ETC feature is
based around a driver demand torque that is deliver ed as an output shaft torque through the correct
positioning of the throttle plate. The Independent Plausibility Check (IPC) feature performs the primary
monitoring function. This resides within the main microprocessor and is responsible for determining the
driver demand torque and comparing it to an estimate of the actual brake torque delivered. If the generated
torque exceeds the driver demanded torque by a speci fied amount, then the appropriate FMEM action is
taken.

With the IPC feature being on the main processor, an intelligent VQZ watchdog is incorporated on a
separate processor to monitor the performance of the IPC and the main processor. If the VQZ determines
that the IPC function is impaired in any way then it takes the appropriate FMEM action.

Electronic Throttle:
DTCs P0606 PCM Microprocessor fault (MIL)
P2110 Forced limit RPM mode (MIL) (Default throttle, if this is the only
code set then it implies that the IPC detected a power greater then demand
occurrence)
Monitor execution continuous
Monitor Sequence none
Monitoring Duration Less than 200ms to register a fault



The Throttle Plate Position Controller (TPPC) controls the throttle plate to the desired throttle angle. It is
embedded within a separate chip within the PCM. The output of the TPPC is a voltage signal to the H-
bridge driver.

Throttle Plate Position Controller:
DTCs P2100 Throttle actuator control motor circuit open (MIL)
P2101 Throttle actuator control motor circuit range/performance (MIL)
(ETB mis-wired, detected at start-up only)
P2107 Throttle actuator control motor processor (MIL) (TP_CMD or H-
Bridge or TPPC self test fault)
P2111 Throttle actuator control system – stuck open (MIL)
P2112 Throttle actuator control system – stuck closed (MIL)
Monitor execution continuous
Monitor Sequence none
Monitoring Duration Less than 1s to register a fault

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
[email protected] AML EOBD Monitors 07 ROC.doc Page 17 of 43

The system monitor also determines the validity of an y inputs to the electronic throttle control feature by
checking for opens, shorts, out-of-range values and inconsistencies.

Throttle Position Sensors:
DTCs P0121 Throttle position sensor A circ uit range/performance (Closed in bore
out of range fault)
P0122 Throttle position sensor A circuit low input
P0123 Throttle position sensor A circuit high input
P0124 Throttle position sensor A circuit intermittent
P0221 Throttle position sensor B circuit range/performance (Closed in bore
out of range fault)
P0222 Throttle position sensor B circuit low input
P0223 Throttle position sensor B circuit high input
P0224 Throttle position sensor B circuit intermittent
P2135 Throttle position sensor A/B voltage correlation
Monitor execution continuous
Monitor Sequence none
Monitoring Duration Less than 200ms to register a fault

Accelerator Pedal Position Sensors:
DTCs P2121 Pedal position sensor D circuit range/performance
P2122 Pedal position sensor D circuit low input
P2123 Pedal position sensor D circuit high input
P2124 Pedal position sensor D circuit intermittent
P2126 Pedal position sensor E circuit range/performance
P2127 Pedal position sensor E circuit low input
P2128 Pedal position sensor E circuit high input
P2129 Pedal position sensor E circuit intermittent
P2138 Pedal position sensor D/E voltage correlation
Monitor execution continuous
Monitor Sequence none
Monitoring Duration Less than 200ms to register a fault

Brake Pedal Switches:
DTCs P0504 Brake switch A/B correlation (BPS on when BLS is off)
P0571 Brake switch A circuit (BPS failed)
P0703 Brake switch B circuit (BLS failed)
P1572 Brake system input failure (BLS failed then BPS failed)
P1703 Brake switch out of self test range (Set when brake is on for KOEO
test or when brake on or off state is not seen for KOER test)
Monitor execution continuous
Monitor Sequence none
Monitoring Duration Not time dependent

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009



Dual MAF Diagnostic
Dual MAF Hardware

The V8 uses a common dirty air pick-up, which feeds twin air filters and MAF meters before recombining the two air streams in a junction prior to the throttle.
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FilterFilter

Filter Filter

Filter Filter

Filter Filter

MAF
meters















Normal Operation Side Wind or Partial
Blockage Backflow
Total Blockage
MAF meters receive an
equal share of the airflow. One MAF meter receives
an airflow greater than the total engine consumption. One MAF meter
receives airflow equal to the total airflow.
MAF meters receive
unequal airflows. This is due to severe side
wind. Fault judgement is
de
pendant on severity.
This can either be due
to a side wind or a partial blockage. One MAF meter will
measure zero airflow and this needs to be
determined to prevent false circuit faults.
Low engine airflow
conditions are
particularly susceptible to side wind. Fault judgement is
dependant on severity.
Fault judgement is
dependant on severity.