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TomT
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Delivery Date: 01 Mar 2011
Leaf Number: 000360
Location: California, now Georgia
Contact: Website

Re: Stuck Throttle?

Yes, that is true for most modern vehicles. Remember the reports of Toyota's laptop and downloading of data after the various Toyota and Lexus run-away incidents...
lincomatic wrote:I forgot to mention something interesting the engineer told me. He said the car has a data logger that collects data only when triggered by a DTC. The dealer doesn't have access to the data, only Nissan can get to it. My car had no DTC's, so no data.
Leaf SL 2011 to 2016, Volt Premier 2016 to 2019, and now:
2019 Tesla Model 3; LR, RWD, FSD, 19" Sport Wheels, silver/black; built 3/17/19, delivered 3/29/19.
bradleygibson
Posts: 88
Joined: Fri Jul 01, 2011 7:18 pm
Delivery Date: 30 Jun 2011
Leaf Number: 4680

Re: Stuck Throttle?

lincomatic wrote:I forgot to mention something interesting the engineer told me. He said the car has a data logger that collects data only when triggered by a DTC. The dealer doesn't have access to the data, only Nissan can get to it. My car had no DTC's, so no data.
What's a DTC?
lincomatic
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Joined: Fri Jun 10, 2011 10:01 am
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Leaf Number: 3819

Re: Stuck Throttle?

bradleygibson wrote: What's a DTC?
Diagnostic Trouble Code.
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garygid
Posts: 12469
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Delivery Date: 29 Mar 2011
Leaf Number: 000855
Location: Laguna Hills, Orange Co, CA

Re: Stuck Throttle?

The Nissan "Black Box" must be recording data all the time, in a loop (maybe the last 60 seconds?).
Does anybody know how long?
Or, what info is recorded?

Then, if a Trouble Code occurs, the "BB" will have the "recent" history.

For real bugs (unanticipated, so they do not create Trouble Codes), there should be a CTC (Customer Trouble Code) that one can invoke, perhaps by hitting the Start (or Map, or some other) button quickly 5 times, or some such way to indicate a "strange-happening" has just occured.

------
When we get a micro-SD card in the SOC-Meter, we hope to be able to have our own "Green Box", at least for the selected CAN-Bus.

With our simple, existing three-CAN (EV, Car, and AV) logging hardware, and a small addition to the CAN-Do software functions, we can easily have our own Brown-Box (several-hour) recorder, or even several-day (or many day) recording to a file, or set of files.
Last edited by garygid on Tue Oct 11, 2011 8:24 pm, edited 1 time in total.
See SOC/GID-Meter and CAN-Do Info
2010 Prius
2011 LEAF, 2014 Tesla S85
2018 & 2019 Tesla Model 3
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bradleygibson
Posts: 88
Joined: Fri Jul 01, 2011 7:18 pm
Delivery Date: 30 Jun 2011
Leaf Number: 4680

Re: Stuck Throttle?

lincomatic wrote:
bradleygibson wrote: What's a DTC?
Diagnostic Trouble Code.
Ah, thanks.

That's too bad there aren't any logs to be had...
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LakeLeaf
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Delivery Date: 04 Aug 2018
Location: South Lake Tahoe, California

Re: Stuck Throttle?

lincomatic wrote:I forgot to mention something interesting the engineer told me. He said the car has a data logger that collects data only when triggered by a DTC. The dealer doesn't have access to the data, only Nissan can get to it. My car had no DTC's, so no data.

Yup - I think you've traveled way way into lawyer land.

I can't even begin to imagine the conversations about liability and what information to collect and store and when and what to not collect. I guess it comes with the territory when you are a trillion yen company.
cwerdna
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Joined: Fri Jun 03, 2011 4:31 pm
Delivery Date: 28 Jul 2013
Location: SF Bay Area, CA

freeze frame data

Side note (as someone who knows little about OBD II): (all?) cars w/OBD II when they encounter a DTC will record freeze frame data. Over on Priuschat, we've sometimes had people post the freeze frame data they got. See below for some examples I was able to dig up:
http://priuschat.com/forums/generation- ... ost1372801" onclick="window.open(this.href);return false;
http://priuschat.com/forums/gen-ii-priu ... ost1156603" onclick="window.open(this.href);return false;

Perhaps CAN bus experts can chime in an elaborate...

'22 Niro EV
'19 Bolt Premier (bought back by GM)
'13 Leaf SV w/premium (former)
'13 Leaf SV w/QC + LED & premium (lease over)

Please don't PM me with Leaf questions. Just post in the topic that seems most appropriate.
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aqn
Gold Member
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Delivery Date: 30 Apr 2011
Leaf Number: 1333
Location: Austin, TX

Re: Stuck Throttle?

lincomatic wrote:I don't want to get people too alarmed, because I wasn't in the car to observe what happened, but my wife had a big scare today. She was accelerating onto the freeway and then had to suddenly slow down due to stopped traffic. She hit the brake, slowed to a crawl, and when she released the pressure on the brake pedal, the car accelerated like the throttle was being depressed. She hit the brake again, slowed almost to a stop, and when she let up, it again lurched forwards. Finally, she pressed the brake pedal very hard. This time, the ABS kicked in, and as it was stopping, the front of the car dived...
lincomatic wrote:She said it was scary ... almost slammed into the car in front of her.
lincomatic wrote:Update...
[...]
Also, I discussed the incident again with my wife, and she said the car wasn't just rolling when she let off the brake, that it lunged forwards.
One thing that I'm not getting from your otherwise thorough data gathering and reporting is the temporal aspect of this incident. For me, words like "lunges" connotes "very short interval of time", but the account reads as if this happens over a couple of seconds, not in a small fraction of a second.

How long did this "accelerated like the throttle was being depressed" event last? How about the subsequent "lurch forward" event? How about the "pressing brake pedal very hard" and "ABS kicked in" events? If she was at a "crawl", I can't imagine these events lasting more than a fraction of a seconds each?

The reason I am inquiring is because I wonder if you have/she has previously experienced the "oh my God I have no brakes" feeling for a split second when the re-gen braking switches off completely and the hydraulic/mechanical brakes take over? In my LEAF, when on ECO and less than a full charge, when slowing down from speed to a crawling pace, that cut-over is very detectable. It feels like the brake hydraulic just sprang a leak. The brake pedal sinks for a split second and the car lurches forward (there's that word again!) for a split second. The first few times I felt it, I almost needed a change of underwear! (The cut-over is much less pronounced, almost undetectable in 'D'. I think. I'm not sure because it has been a while time since I drive in 'D'....)

Is there any possibility that was what she experienced, twice, as the car crosses back and forth over the cut-over boundary?
lincomatic wrote:I know the knee jerk diagnosis is that somehow my wife had her foot on both the accelerator and the brake, [...] Also, the relative positions of the brake & accelerator pedals is such that it's not easy to depress them together unintenionally.
Yeah, I don't buy that theory even if she was stepping on both at the same time. Given the LEAF's power and its relatively large brakes, I'd be amazed if the motor can overpower the brakes.
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lincomatic
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Re: Stuck Throttle?

Andy,
1) It was a couple of seconds between each time she pressed the brake
2) I was writing from memory when I said she slowed to a crawl the first two times she pressed the brake ... I just asked her again, and she says it was faster than a crawl, but she didn't look at the speedo
3) When this happened, she had already been commuting 30 mi on a daily basis for over a month, so she was familiar with the feeling of the switchover from regen to regular brakes. The feeling was that of getting thrown back in the car, like when you're accelerating, not like the feeling you get when you're just rolling.
4) She drives in D when on the freeway. The only time she uses ECO is when she first sets off from my driveway in the morning, until she gets near the freeway. The rest of the day, she just uses D.

Again, this is her account of it, I wasn't in the car... just relaying her description of the incident.
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garygid
Posts: 12469
Joined: Wed Apr 21, 2010 8:10 am
Delivery Date: 29 Mar 2011
Leaf Number: 000855
Location: Laguna Hills, Orange Co, CA

Re: Stuck Throttle?

I always drive in D, except by accident.

The Regen to Mechanical braking seems to be essentially undetectable.
See SOC/GID-Meter and CAN-Do Info
2010 Prius
2011 LEAF, 2014 Tesla S85
2018 & 2019 Tesla Model 3
PU: SDG&E
Solar PV: 33 x 225W -> 7 kW max AC
Craigslist: Xm5000Li Electric Motorcycle

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