Crazy California malfunction

FWIW, I understand auto-downshifting is implemented on ALL CURRENT FCARS that use the Getrag 7DCL750 and I believe the DCTs in AMGs, BMWs also do auto-downshifting to select most aggressive gear (SLS also does multiple downshifts while braking).

The OP's claim potentially covers a lot of cars.

 

Sudden unintended acceleration incidents are often posited to involve the simultaneous failure of a vehicle's acceleration and brake systems. Acceleration system factors may include:
Pedal misapplication
Unresponsive (entrapped) pedals
Electronic throttle control or cruise control failure (see drive by wire)
Stuck throttle (unrelated to pedal position)
Shorting of tin whiskers
Diesel engine runaway - excessive pressure in the crank case can force mist of engine lubricant into the intake manifold, which can be burnt in the same fashion as diesel.


Physical analysis conducted on Toyota’s electronic engine control system including accelerator pedal position sensors (APPSs) in 2011 showed the presence of a significant number of tin whiskers. Tin whiskers are elongated or needle-like structures of pure tin that grow from pure tin and tin alloy surfaces. Toyota's APPS were found to use tin finishes. These tin finishes can produce conductive tin whiskers capable of creating unintended electrical failures such as short circuits. The use of tin finish in Toyota's APPS is therefore a cause for concern.[14] Similarly in 2013, materials used in an automotive engine control unit (ECU) from a 2008 Toyota Tundra truck were analyzed. It was found that pure tin with a nickel underlayer was used as the connector finish in the unit, and analysis revealed tin whiskers on the connector surface. Further testing under a standard temperature-humidity cycling showed tin whisker growth, raising additional reliability and safety concerns. These studies show that poor design choices, such as the use of tin finishes, result in unintended failures.[13]

 

MalibuGuy that's great research and it seems we start seeing a light on the end of the tunnel when trying to find out the causes of Simon's accident.

 

my vote goes to brain fart in the software / logic control... since it only happened to me in auto mode only... events were random and impossible to duplicate since... No issues ( yet ) in manual mode... the impression is confusion in the transmission as what to do, there seemed to be a delay in execution of instructions to transmission... my driving conditions were in changing traffic / speeds with constant shifting, on/off throttle...

 

Thank you, MalibuGuy. Tin whiskers are certainly a plausible explanation and may be the answer to the mystery in this case. Hopefully, Ferrari will pay attention.

In a way, tin whiskers can be rather scary for application in fly-by-wire and drive-by-wire devices. Also scary is that they can grow like weeds over time. The reason they can exist today is due to good intentioned efforts to remove lead from electrical devices. Fortunately, the aerospace industry has recognized the tin whisker issue and is hopefully developing alternatives that will be picked up by the automotive industry.

Here is a very interesting article in layman's terms explaining the topic:

Understanding and mitigating tin whiskers | EE Times

 

Simon

There is a quote from Carl Sagan "Extraordinary claims require extraordinary evidence"

What you are claiming is quite extraordinary. Not saying it didnt happen, but it will require extraordinary proof before it is believable.

 

True! Almost requires an autopsy of that California.

 

The electronics in our cars are sensitive to the condition of the battery. Consider replacement if in question.

Have the dealer then do a complete re-set of the cars system.

Next consider replacing stuff (DCT control module and latest software.) It will cost some money and you may argue that you may replace stuff that doesn't need replacement. But your life and safety, and the safety others on the road, are worth more than the money spent.

Otherwise the next time your Cali suddenly accelerates and keeps accelerating, you will regret it.

 

Years back we worked with folks who did research on tin whiskers. Huge problem.
T

 

IMO, the tin whiskers episode with Toyota is mostly a dramatic example of where this design problem can potentially cause serious reliability issues. However, while it is an intriguing development, especially for the curious, it doesn't mean it is a rampant problem with cars. We don't have recalls due to tin whiskers as most recalls nowadays are due to software issues or overly powerful airbags.

If you do an Internet search on DCT complaints, you will find BMW owners complaining about the abruptness of 2nd to 1st gear downshifts, from people who probably have never driven a manual stick-shift before.

If the OP's car works fine shifting in MANUAL mode but not in AUTO mode, then the culprit is most likely the software as both operating modes use the same hardware. Tin whiskers is a hardware problem. Runaway Toyotas (and Audis) were basic automatic "slush-boxes" - they were not complicated DCT Fcars. If the OP's car also has problems working in MANUAL mode, then perhaps there is a hardware issue.

 

Weather was good for driving today and I tried to duplicate the OP's experience while on the back roads this morning. It was sunny and air temp about 14°C, road surface was fairly smooth old asphalt. I still have my 4-year-old PZeros on as my new wheels have still not arrived yet but the Pirellis are in excellent condition.

I was shifting gears manually in SPORT mode but activated the auto-downshift by holding the downshift paddle while braking at the same time. Unfortunately conditions only permitted braking from 80 kph while in 5th gear. I repeated this 5 times and the car stopped quickly every time without surprises. However, on 3 occasions I also tested lifting my foot from the brake pedal while executing the auto-downshift and on one occasion I managed to time it just as the car shifted to 1st gear. On that occasion, the car revved and lurched forward somewhat while my foot was off the brake pedal. However, it resumed braking as soon as I reapplied the brakes and there was no problem stopping the car.

It is possible the OP's car experienced the same thing and at the same time experienced ABS brake failure like what's been called "ICE MODE" by some experts. I recall reading about this phenomenon on FChat and posting some information I looked up on the topic. It's not a Ferrari-only issue and has/can affect passenger vehicle ABS braking systems in general.

Here's the link to the 458 forum thread where I read about this ICE MODE phenomenon.

The information I looked up also referred to the problem being described as the ABS control logic being confused by unexpected sensor readings, at times possibly caused by incorrectly sized tires. I recently had to specify rims and tires for my new wheels, doing the various math myself to make sure I wouldn't end up with ABS problems. The OP mentioned new tires bought in 2016 and I wonder if they are the same size as the OE ones they replaced.

At any rate, be very careful when changing the sizes of tires (and rims).

 

4th Gear, as always, thanks for the interesting and thoughtful post.
The thread you've found seems to identify brake glitches which range from problems due to cold wet pads and rotors, improperly bedded pads, air in the lines, inadequate bleeding, booster failure, and software bugs affecting the ABS system.

If we take this FChatter's original post as accurate, the issue was run away acceleration.
He did not experience sudden loss of the brakes, or a sudden change in brake pedal feel. In fact he states just the opposite that braking was normal.
His car suddenly accelerated without any driver input to the accelerator pedal when the DCT automatically down shifted to first gear. Not only did it force his car into the stopped vehicle, but his car continued to experience positive throttle input causing a second impact.

Unless he has anything more to say, this is a clear case of run away and not brake failure.

 

First of all, I do not take all of the OP's story as being accurate or consistent so our approach to this mishap completely diverge from that point onward.

What does your experience driving manual stick-shift cars tell you about braking and trying to quickly downshift from speed in 7th gear down to 1st gear? It's very tricky to pull off in a smooth manner. What happens when you also lift off the brakes just before the car shifts into 1st gear? If you have experience aggressively driving stick-shift cars, you will immediately know this is a very bad idea. To get the car into 1st gear, you have to do an aggressive rev-match... which in plain terms is a blip of the throttle...which in the absence of braking results in acceleration.

As I said, my car also lurched when I partially duplicated the OP's actions. You should try it for yourself. It's just as easy to do in a 458.

One of the problems with DCT-equipped cars and with Calis especially is that they can be very attractive to novices as well as enthusiasts. They are too easy to drive and for some people, too easy to get in trouble with. Things can go wrong a lot easier and a lot quicker with these cars because some people think it's just pulling paddles. Many new owners of these cars never learned to handle traditional manual-shifting so they don't understand the effects of the gearing.

I don't think there was any runaway acceleration. The OP was taken by surprise by the sudden rev-matching in 1st gear which he unwittingly allowed to accelerate the car when he lifted his foot off the brakes. His car hit the stopped car and who knows what happened next? These cars do not necessarily stall when they stop and the impact of the collision may have confused the OP's actions as well as the reaction of the car's controls. It's very problematic to guess what the driver or the car did AFTER the collision because neither of them are in their normal state. As laymen and not forensic experts, the only thing that we can debate is how the car which should have been in its normal state, collided with the stopped car to begin with.

I also believe Simon wasn't fully truthful about what happened. Look at it this way. It was a cold Spring day in Scandinavia, 10°C max, he's driving with his track-licensed buddy who also owns a Cali, and he does an auto-downshift from 100 kph to a stop sign where someone is already stopped. Why do you think he would do that?

Driving with a car-guy buddy on public roads is always a bit risky because you will likely go faster than normal, you will be distracted and you will want to show off, do stuff you don't normally do. I think Simon only had the car since September 2016. He doesn't have a lot of experience with this car or perhaps even know how to drive a manual stick-shift. Knowledge of how to drive a traditional manual transmission is very useful if you depart from driving in AUTO mode and start selecting gears for the car. If Simon were truly "a very experienced driver" he wouldn't need our advice. He would already know what happened.

 

Absent brake failure, the brakes are strong enough to hold the car against full throttle.

 

4th's observations got me thinking and I think I have seen something similar mostly in the FF.

In 3rd gear in manual mode I slow from 30 to take a 90d right turn onto a side street. Slowing to about 20 right at the middle of the turn I often get an auto downshift and subsequent rev blip. Since I'm in the middle of the turn I'm lighter on the brakes and the rev blip accelerates the car abruptly. No problem if I manual shift to second and take the turn of course. At 20 I'm going considerably faster than approaching a stop sign.

Don't know if the car can do an outlandish rev blip or if something got stuck but the mechanism seems to be there...I've gotten used to the behavior but I normally now manually downshift without thinking about it...

SV

 

All of these stories make me think about how things will sort out when we have autonomously driving cars. Most of the time, things will work better than with most humans behind the wheel...until they don't.

 

Hey, I've got a question. If your Cali's manatino is in Sport and the trans is in AUTO mode, at what speed will the DCT automatically switch from 2nd gear to first?

I bet that shift won't happen until your car is at a standstill.

 

You would be correct if that were the case; however I wasn't in AUTO. It's also different when you hold the downshift paddle when you apply the brakes.

When I tried to simulate the OP's experience I was manually shifting with the Manettino set to SPORT mode (see excerpt below). I drive mostly in manual except when I am in heavy traffic, going through a speed trap area or just tired, and on the way home.

I think the critical issue is the OP lifted off the brakes before his car shifted from 2nd to 1st. When I managed to time it similarly, my car lurched when it briefly accelerated as it shifted to 1st.

 

The OP as I understand him, was that he was in Sport and Auto shift modes. He was not downshifting manually. He was braking. Therefore he would need to come to a complete stop before the DCT would down shift to first.

Then the technically accurate version of the story is that after the car stopped, the downshift to first occurred and then the sudden acceleration began causing the impact. His car then accelerates again and causes the second impact.

I find this scenario hard to believe.

But for the sake of discussion I decided to look this since there was a run away problem with toyotas.

 

Tried the experiment this a.m. in a big empty parking lot. It was pretty low, 1 - 3 mph.
T

 

Thanks for confirming what I believe to be true as well.

Anyway, if this persons car suddenly accelerates then I think it is fair to say that this a problem specific to his old car and not a known glitch which affected the Cali when it was new..

 

My pleasure. It was a little slick from misting out, so I didn't want to do adhesive high speed stops in Sport/Auto mode. But, in the absence of any codes or reproducibility, I would also assume (hope?) it's a one-off incident that Simon's service people can get to the bottom of.
T

 

First of all, I would like to commend MalibuGuy and tomc for their perseverance on getting to the bottom of this problem brought up by the OP. I agree with your points from earlier today.

Secondly, I want to point out we are still lacking information and confused about what exactly happened to the OP. Part of that has to do with the language barrier even though the OP has made a very good effort to communicate in English, which is not his mother tongue. Part of that is the lack of information and confusing terminology being used in our discussion.

TERMINOLOGY CONFUSION
I should take the blame for some of this confusion in terminology because I referred to "automatic downshift feature" which apparently, most people here do not know about. I was not referring to the automatic gearshift matches gears for the semiautomatic DCT when you bring the car to a stop when driving the car like a car with an automatic transmission. By "automatic downshift" I meant the special feature of the current DCT-equipped Fcars whereby you can cause aggressive sequential downshifts, complete with loud rev-matches, by applying the brakes and then pulling back and HOLDING on the downshift paddle while the car sequentially downshifts.

When the OP stated in his first message that his car downshifted from 2nd to 1st gear I immediately assumed he meant he was using this aggressive feature, which is more of a stunt. As both MalibuGuy and tomc stated, the car doesn't actually downshift to 1st gear. The car brakes to a stop FIRST and THEN puts the DCT into 1st GEAR. The only time when it would downshift to 1st is if the driver manually selects 1st gear or via the "automatic downshift" feature, while keeping your FOOT PLANTED ALL THE TIME on the BRAKES.

This is why I discussed the inappropriateness of playing with this feature behind a car that is stopped in front. Unfortunately, nobody else on this forum seems to know what feature I was discussing and did not ask me about it.

WATCH THE ATTACHED VIDEO
At any rate, instead of saying this or that, I decided to make an MP4 video clip of what actually happens when brake to a stop when you drive the Cali like a car with an automatic transmission. It downshifts very smoothly with barely any rev-matching and comes to a dead stop in 2nd gear before it puts the DCT into 1st gear. The car STOPS IN 2ND GEAR.

BTW, due to safety and legal concerns I made this video on private property but there was only so much space so I was only able to get the car up to 54 kph (33.55 mph) in 3rd gear. If your video player has a step function, you can step the footage and see the car downshifts to 2nd gear, 4 secs into the video, when speed dropped to 40 kph (24.85 mph). And then at 7 seconds the car reaches 0 kph and shifts into 1st gear at the same time. At 8 seconds, my car activates stop/start and kills the engine.

After that I lifted my foot off the brakes, which then deactivated stop/start causing my engine to restart and it started inching forward at a 1 kph pace.

So I hope everyone sees and understands what happens when you brake the Cali to normal stop, driving it with the transmission in auto operation. I still don't know what the OP meant exactly in his description of the accident as there are gaps and inconsistencies in his recall. I asked for the police report and some diagram showing how the accident occurred.

MORE FACTS NEEDED
This was not a cheap accident because the "new hood" (replacement) along with the "spoiler" (front splitter?) and "a cooler" (radiator or electrofan?) damage mentioned by the OP. You can imagine the paint jobs, labour costs added on top. If the OP could not explain the accident, I imagine he would be held responsible for the accident. I assume they have "no-fault" insurance in Sweden or else the other driver may also be interested in why the accident occurred.

There is a lot of information about this accident that was not disclosed or discussed. They all potentially have a bearing on how the accident occurred so I am not quick to assume this was in any way a "runaway acceleration". The OP claims his repair shop says "...several accidents have occurred due to strange behavior of the model...", yet I have not seen anyone on FChat coming across any experience like that either personally or from their dealers/service garages. I don't think Ferrari would use entirely difference control software logic for each of the DCTs in their cars as the ensuing software maintenance complexity and costs for supporting multiple completely different software for each car would be prohibitive (and stupid). I was at one time involved in designing and programming very expensive commercial and industrial real-time systems used by the top 10 companies in their respective sectors.

I did mention the possibility of an ABS failure of the "ICE MODE" variety but it does not explain why the OP's car would accelerate after it reached 1st gear because as you can clearly see, the car only shifts to 1st gear after it stopped.

As I said above about MalibuGuy and tomc, it's perseverance that flushes out the facts and the truth. I hope the OP has more perseverance in handling the matter with his insurance company and repair shop than he has shown so far on this forum. You cannot expect Fchat to fill in all the blanks and provide a favourable explanation if you are not willing to provide information that you should plainly have. I am sorry to be blunt but the OP makes very serious claims and is not particularly cooperative when asked questions.

N.B. I'm also attaching 2 JPEGs to show the moment of downshift from 3rd to 2nd (between 41 and 39 kph) as well as the maximum blip of the engine after the DCT went into 2d gear (at 35 kph). It essentially went from 2200 rpm to 2600 rpm, very mild.
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Yeah, I definitely didn't know about automatic downshifting. But, now that I do, I can confidently say that it's something I don't plan on trying out any time soon. Thanks, 4th.
T

 

Interesting 4th. You did get a lurch as the car was coming to a stop by going light on the brakes. Can you get a video of it?

Both my FF and 458 DCTs go to 1st at stop or just before. Below 2mph and a couple of seconds for sure.

I wonder if the second impact wasn't his own knee jerk reaction to the first lurch... also, the impact of low temps and possibly slick roads might make the potential for error recovery very small...

SV