Regen Braking Issue When Turning

[hermans]

Anytime software is enhanced/modified unexpected things can happen. I worked in this field for 31.5 years and it never ceased to amaze me how faithful the law of unintended consequences is.

OBAMA CARE is a prime example......

[hybridbear]

Update: I have now crossed the manhole cover with friction braking definitely in effect. The "feeling" does not happen at all. The friction braking prevents the wheel that is in the air from turning at all so the three wheels that are on the ground provide braking.

Makes sense when on bumpy pavement, but our issue has nothing to do with bumpy pavement.

[murphy]

Makes sense when on bumpy pavement, but our issue has nothing to do with bumpy pavement.

The only thing I can think of is while turning the inside wheel slows down and the outside wheel speeds up. Is it possible that the car is detecting this as the beginning of a spin of the outside wheel (like on ice) and turning off regen braking so it can initiate ABS braking? I do not believe that it is possible for regen braking and ABS braking to coexist.

[jeff_h]

The only thing I can think of is while turning the inside wheel slows down and the outside wheel speeds up. Is it possible that the car is detecting this as the beginning of a spin of the outside wheel (like on ice) and turning off regen braking so it can initiate ABS braking? I do not believe that it is possible for regen braking and ABS braking to coexist.

 

This is what I was getting at in my post a ways above, that it's typical for the behavior to occur for me when turning right into a parking space and the wheels are probably turned about 2/3 of their range and it seems like it causes an issue with the inside and outside wheel being so different that the system may not be expecting it (but should be) and considers it a lack of traction and ABS kicks in to release the brake temporarily. It is a bit freaky the first couple times it happens, but now I'm not surprised at it and chalk it up to competing systems being too smart by half.

[hybridbear]

The only thing I can think of is while turning the inside wheel slows down and the outside wheel speeds up. Is it possible that the car is detecting this as the beginning of a spin of the outside wheel (like on ice) and turning off regen braking so it can initiate ABS braking? I do not believe that it is possible for regen braking and ABS braking to coexist.

This is what I already determined that the issue is, many weeks ago. The problem is that the car shouldn't have a gap in the timing. Our Focus Electric & my parents' C-Max Energi do not have this issue. Our Fusion Energi didn't have this issue until the 15E03 & 14S21 recalls were performed. When the wheel speed reaches a certain level of variation the car decides that regen braking cannot provide safe stopping power since regen happens at the axle & not at the wheel level. Thus, regen braking force must be reduced & the friction brake pads must be used. This transition should be imperceptible, now it is not & the car lurches forward because the regen braking cuts out but the brake pads don't kick in until later.

[jeff_h]

Our Fusion Energi didn't have this issue until the 15E03 & 14S21 recalls were performed.

 

That's strange - mine has done it for quite some time and I didn't get the 15E03 and 14S21 until last week.

[hybridbear]

I asked him about the updating of modules & he said that the car is designed for a "coordinated flash" of the modules, so even if a recall, like 15E03, only mentions updating the PCM, he says that IDS will automatically update 8 modules so that the calibration stays in sync. He was unsure which 8 modules they are exactly that are part of that coordinated flash programming.

Here is documentation for Ford that substantiates what the engineer told me about the coordinated flash. We had missed this SSM before...

Edited October 13, 2015 by hybridbear

[dtw-dave]

Until I read all these posts, I didn't think this problem was repeatable, but taking my wife's car through a series of left-hand turns yesterday, we were both able to perceive it nearly every time. (Never felt it on right-hand turns ... yet.) It seems that the intensity of the feeling seems to vary ... it isn't the exact same experience every time. For our car, there was one time (first week of October 2015) that my wife felt it when coming to a straight stop, which she says was the worst of them all.

 

We've had all the PCM reflashes that were prescribed.

 

At least we kind of know what it is now from reading through this thread, and can better react when we feel it. Thank goodness this site is here and that everyone is sharing their information. Looking forward to resolution!

[hybridbear]

At least we kind of know what it is now from reading through this thread, and can better react when we feel it. Thank goodness this site is here and that everyone is sharing their information. Looking forward to resolution!

I would request that everyone who experiences this file a complaint with the NHTSA. I agree that this is a wonderful community & that we have done a lot to help solve issues for Ford since these cars were introduced in 2012. The more similar complaints that we send to the NHTSA, the higher the likelihood that they will be noticed. Writing the complaints in a way that is factual & professional should have the most impact. Please use this link to file a complaint.

 

The text of my complaint can be found in this post. This post contains what dtw-dave said in his NHTSA complaint. If enough complaints are sent to the NHTSA this may become the subject of a recall. Thanks everyone for your help to make sure Ford knows that this issue needs to be fixed. :worship: :thumbsup:

[dtw-dave]

I wish I had found this thread before I submitted my NHTSA complaint. I'll have to see if I can go in and edit that to remove the notion of unintended acceleration.

 

Meagan or FordService ... no posts from you on this since August 25, 2015 ... anything you can add or update?

 

Thanks.

[FordService]

I wish I had found this thread before I submitted my NHTSA complaint. I'll have to see if I can go in and edit that to remove the notion of unintended acceleration.

 

Meagan or FordService ... no posts from you on this since August 25, 2015 ... anything you can add or update?

 

Thanks.

 

Thanks for reaching out, Dave.

 

Have you had a chance to swing past your dealer to have this checked out? I may have missed it in skimming your posts. As I'm not a technician, I don't have any in depth information about this, nor can I diagnose or suggest repairs. Your dealer's in the best position to assist; once you have an appointment set up, please let me know.

 

Meagan

[Darkside]

I have not had the update either and mine does this as well. Maybe it is more pronounced after the update but I am certain it is already doing what is described here.

[hybridbear]

As I'm not a technician, I don't have any in depth information about this, nor can I diagnose or suggest repairs. Your dealer's in the best position to assist; once you have an appointment set up, please let me know.

The dealerships can't help either. They also do not have any ability to diagnose or suggest repairs. All they can do is send data off to Ford & wait. The lack of competence is ridiculous!

 

The SA at the dealer sent me this message this morning from Ford Corp:

 

I got the report from Jeff from Ford. I will attach his findings to this it is all in caps which is how internal communication is put forth. No one is yelling.

TEST DROVE VEHICLE WITH CUSTOMER. THE CUSTOMER STATES HE CAN FEEL TRANSITION FROM REGEN BRAKING AND HYDRAULIC BRAKING. WHEN DRIVING WITH THE CUSTOMER, THE DRIVING INVOLVED SHARP TURNS AT 15-20 MPH, NEARING AN ABS EVENT. DURING SOME PORTIONS, STEERING ANGLE EXCEEDED 400 DEGREES. THE TRANSITION FEELING WAS MINIMAL AND WAS OCCURING DUE TO THE AGGRESSIVE TURNING AND BRAKING BEING PERFORMED BY THE CUSTOMER. THE VEHICLE IS OPERATING AS DESIGNED.

According to their findings the car is operating as normally at this time. No other test or repairs are to be attempted for this concern.

The vehicle cannot be operating as designed when this behavior was introduced by the 15E03 & 14S21 recalls & when other identical vehicles do not behave this way.

[GrySql]

Whoa! That almost sounds like a cover-up report, "it's the customer's fault" - amazing. I thought something positive would come of this and all you get back is finger pointing at the consumer. Very disappointing.

 

Now what?

[jsolan]

That's very disappointing to hear. My car does this too when I take a corner too fast, but that is the worst possible scenario for this to happen. I nearly missed an exit off the interstate and had to quickly turn while braking. The lack of deceleration is certainly a scary feeling that nearly put my wife into a panic attack.

[lolder]

Prius has had this problem also a while back. The Gen I FFHs do not seem to have it. Very curious.

[tr7driver]

BOO FORD!

[corncobs]

BOO FORD!

+1

 

The data HB recorded shows something odd clearly and many others including myself had that unpleasant sensation of abrupt lack of deceleration.

Getting into position to back into my driveway is definitely not aggressive turning while getting the car close to an ABS event.

 

If it wouldn't be almost Halloween I would have consider this statement a really bad April fools joke.

Edited October 20, 2015 by corncobs

[GrySql]

"TEST DROVE VEHICLE WITH CUSTOMER. THE CUSTOMER STATES HE CAN FEEL TRANSITION FROM REGEN BRAKING AND HYDRAULIC BRAKING. WHEN DRIVING WITH THE CUSTOMER, THE DRIVING INVOLVED SHARP TURNS AT 15-20 MPH, NEARING AN ABS EVENT. DURING SOME PORTIONS, STEERING ANGLE EXCEEDED 400 DEGREES. THE TRANSITION FEELING WAS MINIMAL AND WAS OCCURING DUE TO THE AGGRESSIVE TURNING AND BRAKING BEING PERFORMED BY THE CUSTOMER. THE VEHICLE IS OPERATING AS DESIGNED."

===

You know, what a good way to hide this issue - right in plain sight.

-

• The Ford engineer never mentioned how many instances of brake transfer from Regen to Service brakes, their quality or quantity, just that they occurred when aggressive braking occurred "nearing an ABS event" - how near? If an ABS event was about to happen wouldn't that be the exact time that ALL the braking was required, not a brief lack of braking? At least a smooth transition?

 

• "During SOME portions", how many, when? He states one extreme steering angle, not the angles when the braking transitions took place.

 

• Is 15-20 mph considered fast?

 

• "Transition feeling" - was that by the seat of his pants - the 'feeling' I mean??

 

• "Minimal" - parse 'minimal' for me will you?

-

Very clever legalese, what BS. I say that engineer was sent to quiet the natives.

Edited October 20, 2015 by GrySql

[Texasota]

HB, I'm curious if the engineer's description of the driving was accurate:

 

 

THE DRIVING INVOLVED SHARP TURNS AT 15-20 MPH, NEARING AN ABS EVENT. DURING SOME PORTIONS, STEERING ANGLE EXCEEDED 400 DEGREES. THE TRANSITION FEELING WAS MINIMAL AND WAS OCCURRING DUE TO THE AGGRESSIVE TURNING AND BRAKING BEING PERFORMED BY THE CUSTOMER.

 

was that accurate or was it embellished it to make it sound more severe?

[bdginmo]

For me I can replicate this about 50% of the time descending down a spiral ramp in a parking garage. But for me, the feeling is highly variable in intensity and feels more like a sudden lurch similar to the feeling you get when a normal automatic transmission shifts gears. I haven't yet been alarmed by it or felt it presented a safety issue for me though. This, of course, could be attributed to my specific driving style and other circumstances.

[md13ffhguy]

HB - Too bad you didn't have a dash cam recording with the Ford rep in the car...

[hybridbear]

HB, I'm curious if the engineer's description of the driving was accurate:

 

 

was that accurate or was it embellished it to make it sound more severe?

I was turning a corner with the Ford engineer.

 

Normally when driving & turning from one street to another I do most of my braking before I begin to turn the wheel, while turning my foot is moving from the brake to the accelerator, and then I'm accelerating before I straighten out the steering wheel. In this scenario I don't feel the surge because there's no need to transition away from regen because I'm not braking with the steering wheel turned.

 

With the Ford engineer I kept my foot on the brake all the way until the car stopped. Most commonly I notice it when turning into a parking lot. In that case I begin braking while going straight, but continue braking with the steering wheel turned. Since I'm braking with the wheel turned, the car must blend in the friction brakes to maintain stability.

 

With the Ford engineer we drove around the cul de sac behind the dealer. I would turn from W 96th St on to Aldrich Ave S. I'd get my speed up to about 20-25 MPH before beginning to brake & turn. I would keep my foot on the brake from just before I started turning the steering wheel all the way until the car came to a stop on Aldrich Ave. I was braking gently, being careful to not exceed the regen limit.

 

I'm not sure how steering wheel angle is measured, but to turn a corner you definitely aren't turning the steering wheel inside the car 400 degrees. Perhaps he's referring to when I made a U turn in a parking lot & had to crank the wheel all the way with the 400 degrees comment.

 

I spoke to the SA on the phone & he said that the case is closed as far as Ford is concerned & that the dealership has been instructed to not do anything else about my concerns. He said that I should contact Ford directly if I am not satisfied.

 

Hello... @FordService... are you there??? I sure miss Ashley. She was our first FordService rep on the forum & she seemed to be the only one who actually cared & bothered to try. Remember all the things Ashley found out for us?? Oil viscosity, detailed technical explanations of how things worked... The cynical side of me thinks that she did too good a job of providing customer service so Ford took her away.

Edited October 21, 2015 by hybridbear

[Texasota]

Normally when driving & turning from one street to another I do most of my braking before I begin to turn the wheel, while turning my foot is moving from the brake to the accelerator, and then I'm accelerating before I straighten out the steering wheel. In this scenario I don't feel the surge because there's no need to transition away from regen because I'm not braking with the steering wheel turned.

That is exactly how I brake/turn and I suspect most drivers also do it this way. This probably explains why I have never noticed this phenomenon in my 2015 or maybe my 2015 does not do it.

 

With the Ford engineer we drove around the cul de sac behind the dealer. I would turn from W 96th St on to Aldrich Ave S. I'd get my speed up to about 20-25 MPH before beginning to brake & turn. I would keep my foot on the brake from just before I started turning the steering wheel all the way until the car came to a stop on Aldrich Ave. I was braking gently, being careful to not exceed the regen limit.

That does not sound like the car was nearing an ABS event as the engineer described it. I think of an ABS event as when the tires begin losing traction and the brakes begin pulsating to regain traction. Maybe my understanding of an ABS event is incorrect.

[Hybrider]

... I think of an ABS event as when the tires begin losing traction and the brakes begin pulsating to regain traction. Maybe my understanding of an ABS event is incorrect.

 

I was thinking this same thing, that you are either _in_ an ABS event, or you are _not in_ an ABS event.

 

I would think that it would take someone a whole lot of ride time, in a whole lot of different cars to know when any particular car is "nearing an ABS event", especially under various different driving conditions. I would think that even within the same model year of FFHs, each FFH would enter into an ABS event at differing points, even with the exact same scenario of driving conditions, which would be practically impossible to replicate exactly twice in a row, even in the same car.

Edited October 21, 2015 by Hybrider