cdub
Well-known member
Got the service done this morning. Took just under 2 hours. Thanks Glendale Nissan!
411 on volontary recall P1273 LEAF VCM LBC TCU NTB12-014
- Thread starter ericsf
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adric22
Well-known member
Ingineer said:
Well, first of all.. false alarm.. the issue still exists. I did some more experimenting and was still able to reproduce it. Not as easily as before, for some reason. I determined the key is to press the throttle very quickly, but not very far. Before you know it, you'll be at full throttle even though the pedal is only pressed down about 5% or 10% of the travel distance.
IBELEAF
Well-known member
it's not an issue, it's a feature :lol:
Leafboy
Well-known member
OK, back to the recall. Something strange has been happening recently. A few days ago my screen just blanked out, but the radio was still playing. It would not turn off either. After reboot, it started to function as normal. Today when I started the car and selected "yes" as I usually do, the screen used to default to the map. Now it has a block on the bottom half of the screen saying "No Route". Pressing the Status button now scrolls through different items in the new block on the screen. One is "Climate Control Off" or Climate Control On". Another has power info and a vertical meter on the right that says "Instant Power" with a scale of 0 thru 8. Pressing the accelerator causes the meter to peg on the 8 and it will not return to 0 until the car completely stops. Another has radio information, that is shown at the top of the screen anyway. I used to get my "meter screen" with the dials showing power use and regen, climate control use and misc power use. Could not find that screen anymore until I started to play with the menus. Now I have to select the menu button, information and then another screen I can't remember now. But it boils down to there are some changes in how to get to some of the screens I like now. Used to get to the power meter screen in two selections and now it takes 3 to get the one I want. SO do you think I have been "hacked" by CarWings??
A pet peeve of mine is I think the screen should default back to the screen you last selected when you turn the car off.
A pet peeve of mine is I think the screen should default back to the screen you last selected when you turn the car off.
lpickup
Well-known member
I think you just got it into a different mode, that's all. It all sounds normal to me (although I haven't had the upgrade yet). To get to the energy screen you talked about I just hit the blue Zero Emission button in the lower right and hit Energy Info on the screen (upper right). Does that not work for you post-upgrade? To get to the map page, just hit the Map button on the right side of the console.
IBELEAF
Well-known member
I am on my 2nd day after update and I have a feeling that my range per bar slightly got better during the usual daily commute... anyone noticed any difference?
Not to ever doubt Phil. But I found it interesting to read this thread and your comment about the accelerator (aka torque selector) being delayed so that instant torque is not applied. Then this afternoon I happend to click on the Nissan website and saw this on the opening page. It's part of the flash intro.
Notice the 100% instant torque. It made me smile.
I wonder what the jump of the line would feel like it the torque wasn't dampered.
Notice the 100% instant torque. It made me smile.
I wonder what the jump of the line would feel like it the torque wasn't dampered.
Ingineer
Well-known member
100% of the available torque is available. =)
If there was 80kW when you stomped it, you'd instantly break the tires loose. It's not clear to me if the TC would then attempt to act on it. They achieve "limited slip" differential action simply by applying the brakes on whatever wheel is slipping. I would assume if both are, it's going to try to reduce the torque request.
They don't want rotational inertia of the PM rotor suddenly transferring high torques to a driveline that's suddenly regained hard traction after slippage, it could shear off something in the transaxle, a half shaft, or a CV joint. In a "normal" car, there is always the clutch or hydrostatic coupling of the transmission to act as a limiting device, but the Leaf has no such device.
Obviously if one was to bypass or remove the accelerator ramp, the TC cutback could also be inhibited or reduced as well, but it could result in bad things happening!
-Phil
If there was 80kW when you stomped it, you'd instantly break the tires loose. It's not clear to me if the TC would then attempt to act on it. They achieve "limited slip" differential action simply by applying the brakes on whatever wheel is slipping. I would assume if both are, it's going to try to reduce the torque request.
They don't want rotational inertia of the PM rotor suddenly transferring high torques to a driveline that's suddenly regained hard traction after slippage, it could shear off something in the transaxle, a half shaft, or a CV joint. In a "normal" car, there is always the clutch or hydrostatic coupling of the transmission to act as a limiting device, but the Leaf has no such device.
Obviously if one was to bypass or remove the accelerator ramp, the TC cutback could also be inhibited or reduced as well, but it could result in bad things happening!
-Phil
Well, to be fair, you can't produce any power (kW) until the wheels start moving.Ingineer said:
It would be nice to have more power at low speeds but then we're really need a limited slip differential as the additional torque would be hard on the tires. Can be bad enough if you stomp on it going around a corner from a stop, especially if the roads are wet.I've reproduced adric22's behavior before as well (don't have the update yet so can't test to see if it's changed).
But I think that you're analysis may be backwards. My hypothesis is that the pedal is a power percentage pedal, not a torque pedal.
When you punch the pedal halfway down to 50% from a stop, you may be asking for 50% power, but the car is only able to give you less than 50% power because torque is limited. You are getting 100% of the available power at the time (power is limited until to get to 25-30 mph or so, but you do get 100% torque). As you speed up more power is available, but the car still thinks you're asking for 100% power (not 50%), so it keeps on increasing power to 100% even though you're still only asking for 50%.
But, as soon as you let off the accelerator a bit, it recalculates maximum power and drops torque output accordingly. Even a tiny drop in accelerator position results in a huge change in power output - much larger than what you'd expect.
lpickup
Well-known member
I just happened to be out driving this morning at 5am so it was a great time to try to reproduce adric's behavior. I think I was able to. I do think that adric is sophisticated enough to know about how far he's pressing the pedal, but I think my hypothesis is halfway between Phil's and adric's:
What I found is that from a stop you have to put the pedal down pretty far to get 4 bubbles. Much farther down that when you're already moving. When I pushed the pedal down to get 4 bubbles from stop, because of the ramp-up behavior, I suspect that my foot was down to a level that would have normally resulted in significantly more acceleration. Sure enough the bubbles did continue to max and stayed there until I was (fairly quickly) doing more than 60, at which point I chickened out (I was not on a highway). I tried to repeat the exercise again and did find that I got down to one less bubble than the max, although I may have lifted my foot that time. Obviously when you're already moving, you'd have to push the pedal in far less to get up to 4 bubbles (and then maintain that speed). So adric22, I would try to pay attention to where your foot is rather than how many bubbles are lit during your experimentation. It may be further down than you think. I also suspect that the reason you can't recreate the problem in ECO mode is that to get the 4 bubbles you'd really have to have your foot down pretty far and would notice it more easily.
I didn't find this to be particularly dangerous per se because my instinct was to lift my foot anyway once I was up to speed.
What I found is that from a stop you have to put the pedal down pretty far to get 4 bubbles. Much farther down that when you're already moving. When I pushed the pedal down to get 4 bubbles from stop, because of the ramp-up behavior, I suspect that my foot was down to a level that would have normally resulted in significantly more acceleration. Sure enough the bubbles did continue to max and stayed there until I was (fairly quickly) doing more than 60, at which point I chickened out (I was not on a highway). I tried to repeat the exercise again and did find that I got down to one less bubble than the max, although I may have lifted my foot that time. Obviously when you're already moving, you'd have to push the pedal in far less to get up to 4 bubbles (and then maintain that speed). So adric22, I would try to pay attention to where your foot is rather than how many bubbles are lit during your experimentation. It may be further down than you think. I also suspect that the reason you can't recreate the problem in ECO mode is that to get the 4 bubbles you'd really have to have your foot down pretty far and would notice it more easily.
I didn't find this to be particularly dangerous per se because my instinct was to lift my foot anyway once I was up to speed.
palmermd
Well-known member
lpickup said:
I too did some experiments yesterday trying to duplicate this. It exhibits this behavior with far less pedal action. The amount of pedal I found was what is equivalent to 5kW consumption on level ground. Find some level ground and travel about 40mph and your find that you can hold the pedal to keep about 5kW to maintain speed. It is about one bubble of power. Practice stepping on the pedal quickly to get to 5kW. What you will find is you can very quickly step on the pedal to get a 5kW output and the car will maintain speed. Now from a complete stop in "D". Quickly press the pedal to the exact same place (which was jumping to a 5kW output when moving). From a complete stop it will not give you 5kW, but will ramp to 80kW.
I still want to run a few more tests, so see if I can compare this to what happens if you floor the pedal from the stop. It feels like the ramp may be a little slower, but not by much. Time to get my PC out and figure out how to start logging data on the CANBus.
garygid
Well-known member
The Trottle Position Sensor might be on the CAR-CAN bus, but some related or derived Requested Power value might be on the EV-CAN bus.
An easy experiment is to drive with throttle ON for 1 second, and OFF (foot off) for one second, repeating 30 times, while logging the EV-CAN data. Then, look for the "square wave" by graphing each data byte (with CAN-Do).
The EV-CAN does have RPM (speed) and Battery Pack Current and Voltage (thus total Power, or kW).
One SOC-Meter (with the Logging Port) can easily log the EV-CAN or the CAR-CAN bus, but two channels of logging would be needed to get them both smultaneously.
An easy experiment is to drive with throttle ON for 1 second, and OFF (foot off) for one second, repeating 30 times, while logging the EV-CAN data. Then, look for the "square wave" by graphing each data byte (with CAN-Do).
The EV-CAN does have RPM (speed) and Battery Pack Current and Voltage (thus total Power, or kW).
One SOC-Meter (with the Logging Port) can easily log the EV-CAN or the CAR-CAN bus, but two channels of logging would be needed to get them both smultaneously.
IBELEAF
Well-known member
I am definitely noticing better range per bar with my routine daily driving. Especially noticeable that at freeway speeds of 65+ I would normally use up 3 bars, now I arrive to work with 2 bars used. Can anyone do "scientific" tests of this?
Ingineer
Well-known member
This "feature" doesn't appear to have changed with the firmware. It's not a bug or a problem. If you had to call Nissan customer service while driving and request they change the position of their foot on your car's pedal, then I can see it being a dangerous situation, but as long as YOU are in control of your foot, this is not a problem.
It's very apparent why they did this, and they clearly understood and took advantage of the psychology of human interpretation of speed and pressure. It works to make the car seem faster and more responsive in D mode, and more linear and less "trigger happy" in ECO. Personally, I find it much more intuitive in ECO, so if you find this non-linear behavior troubling, just shift to ECO. You can still accelerate just as fast, you just have to put more foot into it.
-Phil
It's very apparent why they did this, and they clearly understood and took advantage of the psychology of human interpretation of speed and pressure. It works to make the car seem faster and more responsive in D mode, and more linear and less "trigger happy" in ECO. Personally, I find it much more intuitive in ECO, so if you find this non-linear behavior troubling, just shift to ECO. You can still accelerate just as fast, you just have to put more foot into it.
-Phil
Well, I am in a loaner car. I took my leaf in with an appointment for 8AM and since the letter said it would take an hour I waited.
At 11 they told me they were having problems and that they were on the phone with Nissan. I am now driving a Versa. The Leaf may be derived from it but they are miles apart.
Update: They called me 2 hours later and said that the car was ready. Like many, the snow dam was back ordered. Like I care in Southern California.
They would not tell me what the problem was.
At 11 they told me they were having problems and that they were on the phone with Nissan. I am now driving a Versa. The Leaf may be derived from it but they are miles apart.
Update: They called me 2 hours later and said that the car was ready. Like many, the snow dam was back ordered. Like I care in Southern California.
They would not tell me what the problem was.
IBELEAF
Well-known member
drees said:
One thing though I am charging to 80%... so maybe before it was undercharged and now they are either corrected it or allow charging a bit more then 80%...
Ingineer
Well-known member
I can confirm the older firmware charges to a "real" SOC of exactly 80% when it cuts off. The Stored watt-hours on my car last time I looked were 18400 or 230 "Gids".IBELEAF said:
-Phil
Leafboy
Well-known member
WOW, I must have had a senior moment! It is working as it has been...............lpickup said:
Haven't had the dealer upgrade yet either. Not necessarily in a hurry after listening to others experiences.
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