2010 ASTON MARTIN V8 VANTAGE air condition

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
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Catalyst Monitor Operation:
DTCs P0420 Bank 1, P0430 Bank 2 for Series System ( and P0420 Complete
System for 'Y pipe' configuration ).
Monitor execution once per driving cycle
Monitor Sequence HO2S monitor complete and OK
Sensors OK ECT, IAT, TP, VSS, CPS
Monitoring Duration Approximately 900 seconds dur ing appropriate conditions (approximately
200 to 600 oxygen sensor switches are collected).

Typical catalyst monitor entry conditions: Minimum Maximum
Time since engine start-up (70 oF start) 240 seconds
Engine Coolant Temp 160 oF 230 oF
Intake Air Temp 20 oF 180 oF
Engine Load 10%
Throttle Position Part Throttle Part Throttle
Time since entering closed loop fuel 30 sec
Vehicle Speed 5 mph 70 mph
Steady Air Mass Flow 1.0 lb/min 5.0 lb/min
( Note: 25 - 35 mph steady state driving must be performed to complete the monitor )

Typical malfunction thresholds:
Rear-to-front O2 sensor switch-ratio/ Index Ratio > 0.75

Catalyst Monitor temporary disablement conditions (other than entry requirements) :
EGR, Secondary air, Front and Rear O2 sensor, Engine Coolant Temperature, Mass Air Flow sensor, Air
Charge Temperature sensor, Profile Ignition Pickup & Throttle Position monitor failure.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009

Misfire Monitor (continued)


NNM uses a Motorola Star 12 microprocessor in the PCM to perform the NNM calculations. The
Motorola Star 12 is used in all markets for the Ast on Martin application. The neural network size is 23
nodes and 469 coefficients.
Inputs to Neural Net
• Crankshaft acceleration from the crank position (CKP) sensor
• RPM (calculated from CKP)
• LOAD (normalized for air mass and rpm)
• Indication of cam position from camshaft position (CMP) sensor
Output from Neural Net
• Misfire Call: - 0 (indicating no misfire) or 1 (indicating misfire)

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NNM System Hardware Design


PCM MIL


















Generic Misfire Algorithm Processing.


The acceleration that a piston undergoes during a normal firing event is directly related to the amount of
torque that cylinder produces. The calculated piston/cylinder acceleration value(s) are compared to a
misfire threshold that is continuously adjusted based on inferred engine torque. Deviant accelerations
exceeding the threshold are conditionally labeled as misfires.

The calculated deviant acceleration value(s) are also evaluated for noise. Normally, misfire results in a
non-symmetrical loss of cylinder acceleration. Mechan ical noise, such as rough roads or high rpm/light
load conditions, will produce symmetrical acceleration va riations. Cylinder events that indicate excessive
MAF Signal
CKP Signal
Main PPC
Processor
HCS12HCS12LOAD_FG
CKP Signal
Misfire calls, or
Δt’s
Misfire fault counters
Status Flags
CID Signal
Misfire disablements
Profile Learning CKP
-> ACCEL, RPM
CID -> local sync
Signal validation
Profile application
Executes Neural Net
CID Signal

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
[email protected] AML EOBD Monitors 07 ROC.doc Page 9 of 43


Fuel System Monitor

As fuel system components age or otherwise change over the life of the vehicle, the adaptive fuel strategy
learns deviations from stoichiometry while running in closed loop fuel. These learned corrections are
stored in Keep Alive Memory as long term fuel tr im corrections. They may be stored into an 8x10
rpm/load table or they may be stored as a function of air mass. As components continue to change beyond
normal limits or if a malfunction occurs, the long term fuel trim values will reach a calibratable rich or
lean limit where the adaptive fuel strategy is no longe r allowed to compensate for additional fuel system
changes. Long term fuel trim corrections at their limits, in conjunction with a calibratable deviation in
short term fuel trim, indicate a rich or lean fuel system malfunction.


Fuel Monitor Operation:
DTCs P0171 Bank 1 Lean, P0174 Bank 2 Lean
P0172 Bank 1 Rich, P0175 Bank 2 Rich
Monitor execution continuous while in closed loop fuel
Monitor Sequence none
Monitoring Duration 2 seconds to register malfunction

Typical fuel monitor entry conditions Minimum Maximum
RPM Range idle 4,000 rpm
Air Mass Range 0.75 lb/min 8.0 lb/min
Purge Duty Cycle 0% 0%

Typical fuel monitor malfunction thresholds:
Long Term Fuel Trim correction cell currently being utilized in conjunction with Short Term Fuel Trim:
Lean malfunction: LTFT > 25%, STFT > 5%
Rich malfunction: LTFT < 25%, STFT < 10%

Fuel Monitor temporary disablement conditions ( other than entry requirements ) :
None.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
[email protected] AML EOBD Monitors 07 ROC.doc Page 10 of 43

HO2S Monitor

Front HO2S Signal

The time between HO2S switches is monitored after vehicle startup and during closed loop fuel
conditions. Excessive time between switches or no switc hes since startup indicate a malfunction. Since
'lack of switching' malfunctions can be caused by HO2S sensor malfunctions or by shifts in the fuel
system, DTCs are stored that provide additional information for the 'lack of switching' malfunction.
Different DTCs indicate whether the sensor was st uck lean/disconnected (P1131, P1151), stuck rich
(P1132, P1152) or stopped switching due to excessive long term fuel trim corrections (P1130, P1150).

HO2S 'Lack of Switching' Operation:
DTCs Bank 1 – P0132, P2195, P2196
Bank 2 – P0152, P2197, P2198
Monitor execution continuous, from startup and while in closed loop fuel
Monitor Sequence none
Sensors OK TP, MAF, MAP, ECT, CHT, ACT, IAT
Monitoring Duration 30 to 60 seconds to register a malfunction

Typical HO2S 'Lack of Switching' entry conditions : Minimum Maximum
Throttle Position part throttle
Idle State (not at idle, part throttle)
Engine Load 20% 60%
Time since engine start-up 180 seconds
Inferred Exhaust Temperature 800 oF

Typical HO2S 'Lack of Switching' malfunction thresholds:
< 5 switches since startup after 30 seconds in test conditions
> 60 seconds since last switch while closed loop
> 30 seconds since last switch while closed loop at Short Term Fuel Trim limit

HO2S lack of switching temporary disablement conditions (other than entry requirements) :
Air Charge Temperature, ACT (or IAT) < -20 °F (minimum Cold Climate Test Temperature).
Failure of the sensors mentioned in the above “Sensors OK” section.

The HO2S is also tested functionally. The response rate is evaluated by enteri ng a fixed frequency square
wave, fuel control routine. This routine drives the air/fuel ratio around stoichiometry at a calibratable
frequency and magnitude, producing pr edictable oxygen sensor signal amplitude. A slow sensor will show
a reduced amplitude. Oxygen sensor signal amplitude below a minimum threshold indicates a slow sensor
malfunction (P0133 Bank 1, P0153 Bank 2).

HO2S Response Rate Operation:
DTCs Bank 1 - P0133, Bank 2 - P0153
Monitor execution once per driving cycle
Monitor Sequence none
Sensors OK ECT, IAT, MAF, MAP, VSS, CKP, TP, CMP, no misfire DTCs
Monitoring Duration 4 seconds

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
[email protected] AML EOBD Monitors 07 ROC.doc Page 11 of 43

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
[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



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.
[email protected] AML EOBD Monitors 07 ROC.doc Page 18 of 43


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.

AML EOBD System Operation Summary

Rory O’Curry Aston Martin Lagonda CONFIDENTIAL 1 May 2009
Fault Matrix
ConditionMAF 1 + MAF 2 = EST
MAF 1 = ½ EST
MAF 2 = ½ EST
MAF 1 < MAF 2
MAF 1 low voltage
MAF 2 low voltage
MAF 1 high voltage
MAF 2 high voltage
MAF 1 > EST
MAF 2 > EST
MAF 1 = MAF 2Air Charge P-codes
Normal operating. YY--------f(maf_raw)
None
MAF 1 partly blocked. N-N----f(maf_raw)
P010F, P0100
MAF 1 fully blocked @ low load.
Y-N---- f(maf_raw)
P010F, P0100
MAF 2 partly blocked. -N-N- - -f(maf_raw)
P010F, P010A
MAF 2 fully blocked @ low load. -Y-N---f(maf_raw)
P010F, P010
AMAF 1 shorted to ground.
-Y-N----f(maf_raw)
P0102
MAF 1 shorted to high. -N-Y----f(maf_raw)
P0103
MAF 1 failed in range. -N-N----f(maf_raw)
P0101
MAF 2 shorted to ground. --Y-N---f(maf_raw)
P010C
MAF 2 shorted high. --N-Y---f(maf_raw)
P010D
MAF 2 failed in range. --N-N---f(maf_raw)
P010B
Estimated value wrong. --
Yf(maf_raw)None
MAF 1 and MAF 2 failed in range. --Nf(fmem)
P0101, P010B
Backflow via MAF 1. -
Y-f(fmem)
P0104
MAF 1 short to ground MAF 2 failed in rng. -N-f(fmem)
P0102, P010B
MAF 1 shorted high, MAF 2 failed in rng. -NN
YN---f(fmem)
P0103, P010B
Backflow via MAF 2.Y-- f(fmem)
P010E
MAF 1 failed in rng, MAF2 short to ground. N- -f(fmem)
P0101, P010C
MAF 1 failed in rng, MAF 2 shorted high. NNN
Y---f(fmem)
P0101, P010D
MAF 1 & MAF 2 shorted to ground. -YYNN---f(fmem)
P0102, P010C
MAF 1 & MAF 2 shorted high. -NNYY---f(fmem)
P0103, P010D
Severe backflow via MAF 2.Y-- f(fmem)
P010E
MAF 2 fully blocked @ high load N- -f(fmem)
P010F, P010B
Severe backflow via MAF 1. -
Y-f(fmem)
P0104
MAF 1 fully blocked @ high load. -N-f(fmem)
P010F, P0101
YNNY N
N
NN - NNNN
-
-NYY N
-NYNN
-YNN
Y
N
NY
Y
NN
YN
























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