Hard reset

[acdii]

So if I were to get a new car in March, and the weather is cold, I'm probably going to get bad mileage forever unless I do a hard reset in the spring?

Not necessarily, If you can maximize the FE when you first get the car, then once the warm weather kicks in and the fuel blends have less benzine in it, then the MPG will climb. If you can get 38 in the cold weather. you should have no problems getting 43+ in summer.

 

I say 38-43 since it is what I get on average which is mixed city highway with lots of hills and stops. If your trips are at lower speeds with flats and fewer stops it can get much higher.

[bradycl98258]

Okay, so here are my questions about hard resets, because I've been really curious about this for a while. I apologize if this is FAQ, but I haven't stumbled upon any rock solid explanations yet.

 

At the 10,000 foot level:

Got my 2014 HyTi in late December with 44 miles on it, and reporting 17(!) MPG lifetime as of that moment.

I'm up around 3300 miles now, and my lifetime MPG (preserved on Trip2) is right about 40.

Our weather in Western WA, while nothing compared to many of you, has still been largely in the upper 30's and low 40's up until the last couple of weeks.

 

So while that initial 44 miles before I got the car is fairly statistically insignificant now, is that awful 44 miles possibly still influencing my car's performance in a way that only a hard reset could address?

 

At the detailed nitty-gritty level:

What data exactly (or as exactly as we know) is being gathered after a hard reset? And what exactly (or as exactly as we know) is being done with that data? What characteristics of the car are being controlled using this data?

[GrySql]

A. I apologize if this is FAQ, but I haven't stumbled upon any rock solid explanations yet.

 

B. So while that initial 44 miles before I got the car is fairly statistically insignificant now, is that awful 44 miles possibly still influencing my car's performance in a way that only a hard reset could address?

 

C. What data exactly (or as exactly as we know) is being gathered after a hard reset? And what exactly (or as exactly as we know) is being done with that data? What characteristics of the car are being controlled using this data?

A. I don't believe anyone has answered that exact question in a comprehensive way. If they did it's buried in a post somewhere.

 

B. Probably not too much, your mileage seems good for the conditions since you've had it.

 

When my car had <2000 miles it flashed the MIL (Malfunction Illumination Light) showing several DTC's (Diagnostic Trouble Codes).

The Dealer had no explanation for them and did a Hard Reset to 'clear the modules'.

I asked what procedures were used, the answer was 'both batteries were disconnected and reconnected' following the instructions from the Ford Engineering Hotline.

That was my first reset.

 

My second reset experience was after the PCM update and the components weren't playing nice, my mpg's tanked.

After I did the 100% SOC Hard Reset things seemed to work better and the cars mpg's returned to what I was getting prior to the reset.

I told that to my Service Writer and he said his Tech thought that was a good idea, whatever that meant.

 

C. Don't know exactly.

Try reading that link I pointed to earlier. (Preliminary 2013 MY OBD System Operation Summary for Plug In and Hybrid Electric Vehicles)

It has entries like this:

The Hybrid Electric Vehicle Control System uses four modules to control hybrid electric powertrain functions:

The Engine Control Module (ECM) monitors driver inputs and controls engine related functions.

The Hybrid Powertrain Control Module (HPCM) interprets driver inputs and controls energy management and generator and motor functions.

The Battery Energy Control Module (BECM) controls the high voltage battery pack.

The Brake System Control Module (BSCM) monitors driver braking requests and controls the braking functions.

All these modules use CAN communication for all diagnostic functions and normal-mode communications.

 

I believe that when the batteries are disconnected the Keep Alive Memory (KAM) is erased and all those modules above are restarted when the batteries are reconnected.

The KAM module has a separate wire going to the PCM.

DTC's are not affected by a reset.

(FTA - "A permanent DTC can not be erased by a KAM clear (battery disconnect). Additionally, its confirmed DTC counterpart will be restored after completion of the KAM reset (battery reconnect)".

 

As far as "what is done with that all that data" I think algorithms such as the Exponentially Weighted Moving Average (EWMA) and Step-change Logic (SCL) filters and monitors the data looking for malfunctions.

That is how DTC's are found and set. The data is also analyzed for the various displays and cabin functions and a myriad other necessities.

-

It would be nice to have a Ford Engineer answer your questions, I am a very poor substitute.

Say, maybe Ashley can ask a Ford Engineer for us... oh, Ashley?

[acdii]

Fuel management, battery management, throttle parameters are just a few of the parameters used. It takes the inputs from the driver, and builds a series of tables for air/fuel ratios, Throttle positions, Fuel octane, O2 ratios, temps, etc. Throttle position is a biggie, the more throttle you use, the more fuel it needs, and it learns this is your driving technique and tries to manage the systems based on this. If you are very light on the throttle, it builds a different table. This is the same on all cars, where the FFH is different is the battery management system. It learns your braking techniques, and battery cycles so that it can maintain peak charge rates.

 

Disclaimer, this is based on theory and years of working on cars, and playing with tunes for diesels.

[GrySql]

Disclaimer,

A Disclaimer?

Your arm must be hurting, get well soon and Happy Birthday!

We need you back in fighting trim...

 

[Texasota]

Sounds like this discussion is hinting at the theory discussed in another thread about the FFH learning "bad habits" from inefficient driving styles resulting in worse MPG. In that thread skepticism was expressed by some forum members questioning why Ford would build software into the FFH that would behave this way and potentially put the FFH at a MPG competitive disadvantage.

 

I have no technical expertise or knowledge at all in regards to the "bad habits" theory (don't yet own a FFH) but I also find myself falling into the skeptic category when I consider the implications for performance evaluation tests. Take for example typical performance tests performed by various car rags such as Road and Track, Motor Trend, and many others including Consumer Reports. In those tests they perform numerous acceleration tests, braking tests, emergency handling tests, slalom tests, and fuel efficiency tests. These tests are often performed over and over on the same car that is made available by Ford to the trade rags. That car would certainly have learned very bad habits according to this theory which would then torpedo the fuel efficiency tests.

 

In the case of Consumer Reports they always anonymously purchase their cars brand new and presumably with very few miles on them. If CR was to do the acceleration tests, braking tests, emergency handling tests and slalom tests first, then again the car would learn very bad habits which would again torpedo the subsequent fuel efficiency tests.

 

If this theory is true, then it seems like Ford engineers would have knowingly designed software that would result in less than optimal results when performance and fuel efficiency tests are performed. This is why I am skeptical that this software would result in any kind of a measurable degradation in MPG.

[FordService]

... It would be nice to have a Ford Engineer answer your questions, I am a very poor substitute.

Say, maybe Ashley can ask a Ford Engineer for us... oh, Ashley?

 

GrySql,

 

I've checked with my technical adviser on a couple of similar questions and, unfortunately, the driving strategy and engineering details of how the car operates are considered proprietary information and we're unable to go into detail about these topics. Sorry!

 

Ashley

[GrySql]

If this theory is true, then it seems like Ford engineers would have knowingly designed software that would result in less than optimal results when performance and fuel efficiency tests are performed. This is why I am skeptical that this software would result in any kind of a measurable degradation in MPG.

There are two scenarios here, the first being the theory that you so carefully explained and are skeptical of.

It is theory, and has had some anecdotal success with improving poor mpg FFH's but is not a sure-fire cure for all FFH's, there are too many variables.

I can't explain this, and as you can see, neither will Ford.

 

The second situation is when the car is performing nominally and then for some reason the mpg's degrade or the MIL shows DTC's.

That is what happened to me. In both cases a the car was brought back to it's prior correct operating status by doing a (1) Hard Reset and (2) 100% SOC Hard Reset.

In my case, the car regained it's ability to attain good mpg numbers. Hooray!

So, my friend without a FFH, there is no perfect answer, it is case by case and in mine, it worked.

[lolder]

Adaptive transmissions have been around a while. If you're a lead foot it learns higher rpm shift points which is bad for mileage but good for performance. I don't think hybrids suffer from those limitations. The system is always trying to get the lowest fuel consumption. If you use a lot of power, you get out of the low fuel usage zones of the engine and you use more EV assist both of which reduce economy. As soon as you stop bad habits it should not remember them.

[tr7driver]

I'm not sure how this applies to the FFH, but I can say from experience that cars learn and adapt from being driven.

 

I have a custom tune for my 05 Mustang GT (actually two tunes, one for the track and another for road use) that was created by a speed shop (Anderson Ford) dyno testing the car. (I'd tell you more but Ashley would have to kill me and you.) Over time, actually, over the miles, the car adapts to my driving style and the tune variants change, changing the performance characteristics of the car. I periodically have to reload the tune into the car's computer to return the car to the settings determined by the dyno testing using an x-cal tuning tool that plugs into the ODB2 port. (I can't wait until spring to wake that Mustang up from her winter slumber)

 

I Imagine a hard reset would have a similar effect, returning the learned variants to the factory settings. It would be interesting to see what dyno tuning could do for a FFH. My tuner is mated to the computer on my Mustang, otherwise I'd consider plugging it into the FFH and observing how its reading of the car's settings change over time. I have a cheap ODB code reader from Harbor Freight, but it doesn't give much other information from the computer in the car.

 

I did a hard reset on my FFH 2 weeks ago and did see a slight bump in MPG. I wasn't at 100% SOC (I couldn't find instructions for confirming SOC), so I didn't expect huge results. Temperatures have been mostly in the teens, and I get a larger bump in mpg from managing the climate control than any other action. When its -11F its hard to tell the wife I'm turning off the heater, lol. But when I do I can easily achieve 40 mpg on short/moderate trips, so I have high expectation for this car come spring.

[GrySql]

I did a hard reset on my FFH 2 weeks ago and did see a slight bump in MPG. I wasn't at 100% SOC (I couldn't find instructions for confirming SOC), so I didn't expect huge results.

Doing a 100% SOC is simply sitting parked and using the gas pedal to keep the ICE running until the blue HVB SOC bar is at the top, maxed out.

Then turn the car off and disconnect the two batteries for several (10?) minutes. Reconnect the batteries and you are done.

 

[acdii]

Adaptive transmissions have been around a while. If you're a lead foot it learns higher rpm shift points which is bad for mileage but good for performance. I don't think hybrids suffer from those limitations. The system is always trying to get the lowest fuel consumption. If you use a lot of power, you get out of the low fuel usage zones of the engine and you use more EV assist both of which reduce economy. As soon as you stop bad habits it should not remember them.

Said so eloquently. Pretty much what I was trying to say.

[Texasota]

So, my friend without a FFH, there is no perfect answer, it is case by case and in mine, it worked.

I hope to soon correct that shortcoming. If only my many other shortcomings were so easily resolved...

[Drewbabich]

Will a hard reset clear the stored traction control codes that my 2011 Lincoln mkz hybrid has from driving on a flat tire?

 

Currently it says service power steering and service advancetrac.

 

I lost the power steering when we restarted the car after putting the donut on.

 

We have since replaced the tire and tpms light went away so that problem is fixed.

 

I'm trying to clear the traction control codes without having to take it to a dealer