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Discussion Starter #1
Is there a fuse you can pull to cancell these codes or do you have to use a Predator please ?
 

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Discussion Starter #3
Thanks joey I will give it a try
 

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Discussion Starter #4
No Joy ! I pulled fuse 11 but the light is still on & EVIC showing : P0128 I have replaced the thermostat & it now runs at the correct temprature . Any other ideas please ?
 

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Hmm.. I have had many P0128's and I am almost certain pulling fuse 11 cleared the code.
With engine off, did you pull it out for about 15 seconds, and then reinsert the fuse?
The only other idea is to disconnect the battery for about 15 seconds.

The P0128 will eventually clear itself after so many "good trips", which I think is 3.
But getting 3 good trips is more complicated than just 3 starts with normal engine temps/warm-up. It took me a couple of weeks before my car cleared the P0128 on its own.

To avoid the P0128, try to warm your car up longer, and begin your drive with shifter in 4th gear.
You need to get your temps above 170 degrees (or was it 180 degrees?) within the first 10 minutes or so.
 

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Discussion Starter #6
Cheers joey , 3 good trips is easy for me as the car is a daily driver & I drive all over the UK so I will see what happens after a few drives
 

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I bought an OBDII scan tool from Canadian Tire on sale for $120 can.
Looks up code, tells you what it means, and can clear them.
Minor error codes usually clear if it doesn't re-occur during the next three consecutive runs.
 

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Cheers joey , 3 good trips is easy for me as the car is a daily driver & I drive all over the UK so I will see what happens after a few drives
To prevent the codes, drive (and/or warmup) about 10 minutes before you get on a highway.
I doubt anyone gets a P0128 if they are only city driving.
I always got my P0128's on very cold mornings/evenings when I get on the freeway a few minutes from my house/work.

How the PCM's calculates a "good trip" is not obvious. I read it the Service Manual, or somewhere.
There are a bunch of factors, besides coolant temp, that the car considers before it counts a trip as good.
When I get home from work I will see if I can find the explanation of a "good trip".
 

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Discussion Starter #9
Problem is like tomorrow I leave home at 4.30am ( not a good time of the day to have the magnaflows burbling on the driveway ) , I live less than a mile from the Motorway/freeway but I try not to take it over 2000rpm untill it reaches working temperature , 95 mile round trip in the morning so I hope this is going to be one of the three
 

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Here is the Service Manual explanation of Good Trips, and more.
I believe a P0128 is a Priority 3 DTC and requires 2 consecutive bad trips to set the MIL.
I need to read this a few more times to figure out how 3 good trips, and 40 consecutive warm-up cycles are related.
I believe I tried 2 times to let the P0128 clear itself. One time I think it took about 4 days, and maybe 15 different trips. The other time I waited about 2 weeks or more and I got tired of waiting and cleared the code myself.
I used the Predator to clear the code, but I am almost certain pulling Fuse 11 will clear the code.


TASK MANAGER
DESCRIPTION
The PCM is responsible for efficiently coordinating the operation of all the emissions-related components. The PCM
is also responsible for determining if the diagnostic systems are operating properly. The software designed to carry
out these responsibilities is call the “Task Manager”.
OPERATION
The Task Manager determines when tests happen and when functions occur. Many of the diagnostic steps required
by OBD II must be performed under specific operating conditions. The Task Manager software organizes and prioritizes the diagnostic procedures. The job of the Task Manager is to determine if conditions are appropriate for
tests to be run, monitor the parameters for a trip for each test, and record the results of the test. Following are the
responsibilities of the Task Manager software:
² Test Sequence
² MIL Illumination
² Diagnostic Trouble Codes (DTCs)
² Trip Indicator
² Freeze Frame Data Storage
² Similar Conditions Window

Test Sequence
In many instances, emissions systems must fail diagnostic tests more than once before the PCM illuminates the
MIL. These tests are known as ’two trip monitors.’ Other tests that turn the MIL lamp on after a single failure are
known as ’one trip monitors.’ A trip is defined as ’start the vehicle and operate it to meet the criteria necessary to run the given monitor.’ Many of the diagnostic tests must be performed under certain operating conditions. However, there are times when tests cannot be run because another test is in progress (conflict), another test has failed (pending) or the Task Manager has set a fault that may cause a failure of the test (suspend).

Pending
Under some situations the Task Manager will not run a monitor if the MIL is illuminated and a fault is stored from
another monitor. In these situations, the Task Manager postpones monitors pending resolution of the original fault.
The Task Manager does not run the test until the problem is remedied.
For example, when the MIL is illuminated for an Oxygen Sensor fault, the Task Manager does not run the Catalyst
Monitor until the Oxygen Sensor fault is remedied. Since the Catalyst Monitor is based on signals from the Oxygen
Sensor, running the test would produce inaccurate results.

Conflict
There are situations when the Task Manager does not run a test if another monitor is in progress. In these situations, the effects of another monitor running could result in an erroneous failure. If this conflict is present, the monitor is not run until the conflicting condition passes. Most likely the monitor will run later after the conflicting monitor has passed.
For example, if the Fuel System Monitor is in progress, the Task Manager does not run the catalyst Monitor. Since
both tests monitor changes in air/fuel ratio and adaptive fuel compensation, the monitors will conflict with each other.

Suspend
Occasionally the Task Manager may not allow a two trip fault to mature. The Task Manager will suspend the maturing
of a fault if a condition exists that may induce an erroneous failure. This prevents illuminating the MIL for the
wrong fault and allows more precise diagnosis.
For example, if the PCM is storing a one trip fault for the Oxygen Sensor and the catalyst monitor, the Task Manager
may still run the catalyst Monitor but will suspend the results until the Oxygen Sensor Monitor either passes or
fails. At that point the Task Manager can determine if the catalyst system is actually failing or if an Oxygen Sensor
is failing.

MIL Illumination
The PCM Task Manager carries out the illumination of the MIL. The Task Manager triggers MIL illumination upon
test failure, depending on monitor failure criteria.
The Task Manager Screen shows both a Requested MIL state and an Actual MIL state. When the MIL is illuminated
upon completion of a test for a good trip, the Requested MIL state changes to OFF. However, the MIL remains
illuminated until the next key cycle. (On some vehicles, the MIL will actually turn OFF during the thirdgood trip)
During the key cycle for the third good trip, the Requested MIL state is OFF, while the Actual MIL state is ON. After
the next key cycle, the MIL is not illuminated and both MIL states read OFF.

Diagnostic Trouble Codes (DTCs)
With OBD II, different DTC faults have different priorities according to regulations. As a result, the priorities determine MIL illumination and DTC erasure. DTCs are entered according to individual priority. DTCs with a higher priority overwrite lower priority DTCs.

Priorities
² Priority 1 One-Trip Failure of Non-Fuel or Non-Mis-Fire Fault (e.g., Cat Mon Failure)
² Priority 3 Matured Fault (either One-Trip or Two-Trip) Non-Fuel & Non-Mis-Fire
² Priority 4 One-Trip Failure of Fuel System or Mis-Fire Fault
² Priority 6 Matured Fault for Fuel System or Mis-Fire (either One-Trip or Two-Trip)
Non-emissions related failures have no priority. One trip failures of two trip faults have low priority. Two trip failures
or matured faults have higher priority. One and two trip failures of fuel system and misfire monitor take precedence
over non-fuel system and non-misfire failures.

DTC Self Erasure
With one trip components or systems, the MIL is illuminated upon test failure and DTCs are stored.
Two trip monitors are components requiring failure in two consecutive trips for MIL illumination. Upon failure of the
first test, the Task Manager enters a maturing code. If the component fails the test for a second time the code
matures and a DTC is set.
After three good trips the MIL is extinguished and the Task Manager automatically switches the trip counter to a warm-up cycle counter. DTCs are automatically erased following 40 warm-up cycles if the component does not fail again.
For misfire and fuel system monitors, the component must pass the test under a Similar Conditions Window in order
to record a good trip. A Similar Conditions Window is when engine RPM is within ±375 RPM and load is within
±20% of when the fault occurred.
NOTE: It is important to understand that a component does not have to fail under a similar window of operation
to mature. It must pass the test under a Similar Conditions Window when it failed to record a Good
Trip for DTC erasure for misfire and fuel system monitors.
DTCs can be erased anytime with a scan tool. Erasing the DTC with the scan tool erases all OBD II information.
The scan tool automatically displays a warning that erasing the DTC will also erase all OBD II monitor data. This
includes all counter information for warm-up cycles, trips and Freeze Frame.

Trip Indicator
The Trip is essential for running monitors and extinguishing the MIL. In OBD II terms, a trip is a set of vehicle
operating conditions that must be met for a specific monitor to run. All trips begin with a key cycle.

Good Trip
The Good Trip counters are as follows:
² Global Good Trip
² Fuel System Good Trip
² Misfire Good Trip
² Alternate Good Trip (appears as a Global Good Trip on scan tool)
² Comprehensive Components
² Major Monitor
² Warm-Up Cycles

Global Good Trip
To increment a Global Good Trip, the Oxygen sensor and Catalyst efficiency monitors must have run and passed,
and 2 minutes of engine run time.

Fuel System Good Trip
To count a good trip (three required) and turn off the MIL, the following conditions must occur:
² Engine in closed loop
² Operating in Similar Conditions Window
² Short Term multiplied by Long Term less than threshold
² Less than threshold for a predetermined time
If all of the previous criteria are met, the PCM will count a good trip (three required) and turn off the MIL.

Misfire Good Trip
If the following conditions are met the PCM will count one good trip (three required) in order to turn off the MIL:
² Operating in Similar Condition Window
² 1000 engine revolutions with no misfire

Alternate Good Trip
Alternate Good Trips are used in place of Global Good Trips for Comprehensive Components and Major Monitors.
If the Task Manager cannot run a Global Good Trip because a component fault is stopping the monitor from running,
it will attempt to count an Alternate Good Trip.
The Task Manager counts an Alternate Good Trip for Comprehensive components when the following conditions are
met:
² Two minutes of engine run time, idle or driving
² No other faults occur
The Task Manager counts an Alternate Good Trip for a Major Monitor when the monitor runs and passes. Only the
Major Monitor that failed needs to pass to count an Alternate Good Trip.

Warm-Up Cycles
Once the MIL has been extinguished by the Good Trip Counter, the PCM automatically switches to a Warm-Up
Cycle Counter that can be viewed on the scan tool. Warm-Up Cycles are used to erase DTCs and Freeze Frames.
Forty Warm-Up cycles must occur in order for the PCM to self-erase a DTC and Freeze Frame. A Warm-Up Cycle
is defined as follows:
² Engine coolant temperature must start below and rise above 160° F
² Engine coolant temperature must rise by 40° F
² No further faults occur


Freeze Frame Data Storage
Once a failure occurs, the Task Manager records several engine operating conditions and stores it in a Freeze
Frame. The Freeze Frame is considered one frame of information taken by an on-board data recorder. When a fault
occurs, the PCM stores the input data from various sensors so that technicians can determine under what vehicle
operating conditions the failure occurred.
The data stored in Freeze Frame is usually recorded when a system fails the first time for two trip faults. Freeze
Frame data will only be overwritten by a different fault with a higher priority.
CAUTION: Erasing DTCs, either with the scan tool; or by disconnecting the battery, also clears all Freeze
Frame data.


Similar Conditions Window
The Similar Conditions Window displays information about engine operation during a monitor. Absolute MAP (engine
load) and Engine RPM are stored in this window when a failure occurs. There are two different Similar conditions
Windows: Fuel System and Misfire.

FUEL SYSTEM
² Fuel System Similar Conditions Window — An indicator that ’Absolute MAP When Fuel Sys Fail’ and ’RPM
When Fuel Sys Failed’ are all in the same range when the failure occurred. Indicated by switching from ’NO’
to ’YES’.
² Absolute MAP When Fuel Sys Fail — The stored MAP reading at the time of failure. Informs the user at
what engine load the failure occurred.
² Absolute MAP — A live reading of engine load to aid the user in accessing the Similar Conditions Window.
² RPM When Fuel Sys Fail — The stored RPM reading at the time of failure. Informs the user at what engine
RPM the failure occurred.
² Engine RPM — A live reading of engine RPM to aid the user in accessing the Similar Conditions Window.
² Adaptive Memory Factor — The PCM utilizes both Short Term Compensation and Long Term Adaptive to
calculate the Adaptive Memory Factor for total fuel correction.
² Upstream O2S Volts — A live reading of the Oxygen Sensor to indicate its performance. For example, stuck
lean, stuck rich, etc.
² SCW Time in Window (Similar Conditions Window Time in Window) - A timer used by the PCM that indicates
that, after all Similar Conditions have been met, if there has been enough good engine running time in
the SCW without failure detected. This timer is used to increment a Good Trip.
² Fuel System Good Trip Counter — A Trip Counter used to turn OFF the MIL for Fuel System DTCs. To
increment a Fuel System Good Trip, the engine must be in the Similar Conditions Window, Adaptive Memory
Factor must be less than calibrated threshold and the Adaptive Memory Factor must stay below that threshold
for a calibrated amount of time.
² Test Done This Trip — Indicates that the monitor has already been run and completed during the current trip.

MISFIRE
² Same Misfire Warm-Up State — Indicates if the misfire occurred when the engine was warmed up (above
160° F).
² In Similar Misfire Window — An indicator that ’Absolute MAP When Misfire Occurred’ and ’RPM When Misfire
Occurred’ are all in the same range when the failure occurred. Indicated by switching from ’NO’ to ’YES’.
² Absolute MAP When Misfire Occurred — The stored MAP reading at the time of failure. Informs the user at
what engine load the failure occurred.
² Absolute MAP — A live reading of engine load to aid the user in accessing the Similar Conditions Window.
² RPM When Misfire Occurred — The stored RPM reading at the time of failure. Informs the user at what
engine RPM the failure occurred.
² Engine RPM — A live reading of engine RPM to aid the user in accessing the Similar Conditions Window.
² Adaptive Memory Factor — The PCM utilizes both Short Term Compensation and Long Term Adaptive to
calculate the Adaptive Memory Factor for total fuel correction.
² 200 Rev Counter — Counts 0–100 720 degree cycles.
² SCW Cat 200 Rev Counter — Counts when in similar conditions.
² SCW FTP 1000 Rev Counter — Counts 0–4 when in similar conditions.
² Misfire Good Trip Counter — Counts up to three to turn OFF the MIL.
 

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Discussion Starter #11
Great news , after this mornings run out the code has gone & so has my little engine light . Hoooooray
 

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Should be under the driver side dash by knee area..black rectangular connector...

Sent from my SPH-D710 using AutoGuide.Com Free App
 
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