How to get rid of this mix mode?

[webcontrol]

Yesterday when I drove out from home, outside was 75F degrees, 5 minutes out from home, road was relatively flat, battery showed 30%, speed was about 40 mph, suddenly both gas engine and electrical motor engaged. I tried to step on gas paddle hoping gas engine to take over stop wasting EV battery.  However, it only increased electrical motor output.  I released gas paddle and re-apply, it did the same.  This continued till my EV battery ran low, then switched to gas engine only.

 

I saw this happen many times. I don't understand why.  To me, this is a waste for EV battery.

Edited April 1, 2014 by webcontrol

[Laurel]

I am no car guy, but in my experience with my car your battery at 30% is the issue.  My engine generally kicks in when the battery is that low and your battery will soon recharge.

[hybridbear]

Yesterday when I drove out from home, outside was 75F degrees, 5 minutes out from home, road was relatively flat, battery showed 30%, speed was about 40 mph, suddenly both gas engine and electrical motor engaged. I tried to step on gas paddle hoping gas engine to take over stop wasting EV battery.  However, it only increased electrical motor output.  I released gas paddle and re-apply, it did the same.  This continued till my EV battery ran low, then switched to gas engine only.

 

I saw this happen many times. I don't understand why.  To me, this is a waste for EV battery.

I agree that this is a poor use of gas. When the ICE operates like this the engine is burning more gas per kWh of energy produced, i.e. it isn't operating in its most efficient BSFC region. Shifting briefly into L until you hear the ICE rev will get it to stop doing this. Once you hear the ICE begin to rev you can shift back to D and the car will then use the ICE to charge the HVB.

[ScubaDadMiami]

If you take your foot off of the accelerator, allowing full EV mode, and then tap the pedal sharply enough, that should kick it out of EV and activate only ICE. I even do this when EV+ kicks in. You have to do it sharply and using enough power to goes beyond the EV threshold, but it can be done.

[webcontrol]

Scuba,  thanks.  I tried that, but not sharp enough I guess, it still in mixed mode.  I don't understand the software logic behind this behavior.  I am sure Ford software engineers put in this code for some reason.  If Ford let us know the reason, we can figure out how to avoid enter this mix mode.  To me, if the ICE started, it should run by itself till some other reason caused it to switch to battery.

 

Does this mean Ford engineers purposely want to discharge the battery low enough sometimes?  If so, I think that is a waste, because during normal driving, if they force EV mode will use up battery to low enough anyway, that could be counted as battery drain to low.

Edited April 2, 2014 by webcontrol

[plus 3 golfer]

I think there is a misconception of how much battery capacity is actually used by the algorithms during normal operation, what the battery symbol really is, and trying to save EV for later will results in a significant boost to FE.  Based on my observations, what other's have observed, and common practices used in hybrid operations to ensure battery longevity, the PCM algorithms limit the usable capacity of the high voltage battery to between about 30% and 70% of the maximum battery capacity of 1.4 kWh.  But in normal operation on fairly flat roads at all speeds, I have observed / recorded that generally the state of charge (SOC) of the HVB stays between about 40% and 55% of the capacity.  Very seldom do I see the SOC dropping below 38% and above 65%. There really isn't a lot of usable energy to save for a rainy day. So, 15% of the capacity is only 0.21 kWh (0.15 x 1.4 kWh).  Yet, looking at the battery symbol one would think that the usable energy would be a significantly higher portion of the 1.4 kWh.   

 

The battery symbol display does not represent the SOC of the battery but appears to represent the % of the usable capacity.  I see about the same relationship that hannawcu saw in this post between usable capacity and HVB SOC.  Also, the battery symbol requires a "calibrated eyeball" to read with any degree of accuracy and does one count the tip of the battery symbol or not.  I can say that when the battery symbol appears to show 50% (to me), the SOC is 48+%.  When the battery symbol appears to show about 1/3, the SOC is about 45% and when the battery symbol shows about 2/3, the SOC is about 52%.  When the battery level is about a lines width from touching the top of the battery (not the tip), the SOC reads about 64%.

 

Also, one may think a road is flat but it usually isn't.   I use my Garmin to display elevation while traveling and use Google Earth and topo maps after the fact to see how elevation changes may have affected my recorded data. Small changes in elevation, wind and so forth affect load on the vehicle and how the powertrain algorithm reacts to maintain speed - run ICE, run EV, coast, run ICE and EV.

 

Bottom line is that trying to second guess why the algorithms choose to run ICE instead of EV, EV instead of ICE, or both and to think that operating the powertrain differently would have been better with such limited data is a fruitless exercise.  However, this is not saying that anticipating driving conditions and forcing certain powertrain operations can't improve FE.  Hypermilers anticipate driving conditions all the time to maximize FE.  But I'll say this again, hypermilers typically sacrifice time for FE.  Their average speed is lower than they think as they P&G, coast, and so forth.

 

Below I've posted a trip I recorded recently to show how the SOC changes over 42 miles.  Also note that ECO cruise was set at 55 mph just before the 800 second mark for about 5 miles.  SOC climbed from low 40s to about 58% where it leveled off.  This is the point many refer to as high ICE.  There is virtually no change in SOC and RPM remains fairly constant varying for the slight changes in load.  FE looks to average about 47 mpg into nearly 10 mph sustained wind.  But I wondered why the FE dropped during this period from a high of about 48 to 46 mpg.  Even though the road looked flat during the entire 5 miles, the first part was downhill and the last 1 1/4 miles was flat.

 

Edited April 3, 2014 by Plus 3 Golfer

[RaPieR]

Very cool info thanks Plus 3!

[SnowStorm]

Plus 3, thanks for all the info.  It is good to know that normal driving with SOC constantly going up and down isn't using that much of the capacity as I want that battery to last a long time!  Regarding your comment, "does one count the tip of the battery symbol or not", I have noticed that, when regening down a long grade with CC active, the tip must be filled before you loose speed control and the car starts speeding up.  Have you ever had that happen and noted SOC at that point?

[plus 3 golfer]

Plus 3, thanks for all the info.  It is good to know that normal driving with SOC constantly going up and down isn't using that much of the capacity as I want that battery to last a long time!  Regarding your comment, "does one count the tip of the battery symbol or not", I have noticed that, when regening down a long grade with CC active, the tip must be filled before you loose speed control and the car starts speeding up.  Have you ever had that happen and noted SOC at that point?

Yes, I know it fills up driving down a hill as I have noticed several times. But when assessing the % fill by eyeball, it's natural to ignore it.  Even when I count it, I see an actual 48% SOC when the battery symbol looks to be at 50% counting the tip.  My point is when someone says their battery level was at 30%, one has to question what really was their SOC.

 

My next trip into the mountains I plan to record data and will see what the maximum SOC reaches going downhill (hannahwcu got just shy of 70%).  When I travel in the mountains on steep, long, curvy grades, I use grade assist and Low when descending, shifting in and out to decrease and increase speed.  I virtually never have to touch the brakes (which would likely be friction) or the accelerator.  The battery fills to the tip very quickly going down longer grades but unfortunately I didn't think of recording or monitoring SOC.  Just slowing down from 55 to 7 mph in about 21 seconds spiked the SOC 5.9% points (shown in the graph after the 55 mph ECO cruise). 

[Noah Harbinger]

My next trip into the mountains I plan to record data and will see what the maximum SOC reaches going downhill (hannahwcu got just shy of 70%).  

 

I just want to second that and say that in my data monitoring, I maxed out at 69.8% SOC - the needle got there and didn't budge for entire minutes time during a long downhill drive. 

[HannahWCU]

Yesterday when I drove out from home, outside was 75F degrees, 5 minutes out from home, road was relatively flat, battery showed 30%, speed was about 40 mph, suddenly both gas engine and electrical motor engaged. I tried to step on gas paddle hoping gas engine to take over stop wasting EV battery.  However, it only increased electrical motor output.  I released gas paddle and re-apply, it did the same.  This continued till my EV battery ran low, then switched to gas engine only.

 

I saw this happen many times. I don't understand why.  To me, this is a waste for EV battery.

 

I think I know why this happened.  Was this the first use of the CMax for the day (in other words, was the engine completely cool, ambient temperature)?  If so, this is normal.  See http://fordfusionhybridforum.com/topic/7408-ffh-warm-up-stages/ for a better explanation of the different stages the engine goes through during warm-up (I know this is from the Fusion site, but it uses the same powertrain as the CMax, you can also read the thread on this at this site: http://fordcmaxhybridforum.com/topic/3378-warm-up-stages-for-fusion-hybrid-by-hybridbear-applicable-to-c-max/).  When the CMax First starts the ICE, it will run it at low RPM (basically at idle) until the engine warms up.  The link explains ways around it.  I just go with it.  From my house, I EV to the main road, from there it is about a mile in either direction to the closest stop sign, I kick in the ICE to warm it up during this time since I am moving anyway.  Hope this helps.

Edited April 3, 2014 by HannahWCU

[plus 3 golfer]

webcontrol states 5 miles from home, 75 F ambient.  So, it seems unlikely that coolant temperature never reached 55*C after 5 miles of operation where normal operation will take place especially if one looks at my updated graph below for coolant temperature.  But I guess it's possible.  webcontrol says both ICE and EV ran and thus battery was being depleted when cruising at 40 mph 5 miles from home. I don't believe this is a warm-up condition.  In addition, I scanned my data and can find no instances where ICE ran and battery level didn't rise or basically stay the same (high ICE).  There was never a case where ICE ran and EV was being depleted in normal cruising on flat ground.  Either there is a problem with webcontol's car or he may not really know what he thinks he saw.

 

In my trip coolant started out at 84F (garaged) and dropped to 81F as the ambient air was 70F before starting to climb.  At about 1/2 mile and 50 seconds, coolant was above 40C where the warm-up stage s1(b) likely ended.   At about 110 seconds or about one mile from home I reached 53C.  My speed during this first 110 seconds averaged about 30 mph.  ICE was generally running between about 1500 and 2000 rpm.  ICE also shut down at 107 seconds with speed at 14 mph as I was coming to a stop.  ICE started again at 134 seconds at 1879 RPM and 15 mph.  I reached 55C which is the highest hurdle to clear to end warm-up at the 146 second mark about 1 1/4 miles from the start.  Also, my grille covers were not on my car during this testing.

 

Edited April 4, 2014 by Plus 3 Golfer

[HannahWCU]

Ok your right, I'm wrong. Sorry I tried to help and/or give my opinion. I've been avoiding this forum for a while and now I remember why.

[plus 3 golfer]

Ok your right, I'm wrong. Sorry I tried to help and/or give my opinion. I've been avoiding this forum for a while and now I remember why.

Nothing wrong with expressing an opinion or providing a link to the warm-up operations which is great information.  

 

My opinion is that the warm-up was completed and showed why I thought so.  What is wrong with that?  But, do whatever you so desire to do and for whatever reason.  If you don't like someone responding to your posts, you probably should avoid the forum.  As I've said many times, this isn't Facebook.  

[webcontrol]

+3, thanks for your detailed explanation. One thing I said was 5 minutes into driving, not 5 miles into driving.  I don't know if that making any differences in analysis. I did notice this kind of behavior many times.  My wife and my son both want to drive my C-MAX instead of Lexus SUV we have.  That might cause the adoptive FE algorithm to confuse?  My wife wants to get 60MPG or higher when she driving, my son does not care about MPG only wanting save seconds when he driving. 

Edited April 4, 2014 by webcontrol

[plus 3 golfer]

My mistake. What distance did you travel when you noticed the issue?  Can you initiate this mixed mode anytime?  If so, you may want to go to the dealer and demonstrate it to them.

 

In 5 minutes at a 75F ambient your car should be out of warmup mode.  Even in warm up mode, I've never noticed what you describe as ICE may idle at stop and not shut off  but once you accelerate even in warm-up mode, ICE rpm increases and charges the battery. EV shouldn't run except during acceleration from a stop up to around 15 mph or so.  If you look at the first part of the graph (under 50 seconds), I was in warm up mode.  EV ran while backing, and driving a few hundred feet to a stop sign.  After I turned and accelerated EV stayed on until my speed reached 11 mph (about 21.3 seconds after I left home)  ICE then came on and stayed on until I was coasting to a stop about one mile from home. ICE shut off at 17 mph and coolant temperature was about 53*C.  So, with higher ambient temperatures it doesn't take long to get out of warmup.  Even when the ambient is lower like this morning at 62*C, I was still out of warm-up by one mile from home.  Only when the ambient temp is around 50F or below and the garaged car is at 55 F does it take another 1/2 mile at 45 - 55 mph to get out of warmup mode. 

 

Bottom line is that IMO, your issue does not fit the parameters of warm-up mode.  I think that the way to see what is happening with you car is to buy an iOS or Android App and an ELM 327 interface and record vehicle data .  Otherwise, it's speculation.

[webcontrol]

+3, thanks. Which ELM327 to buy? I noticed there is a with Bluetooth claimed version 1.5, another is non-Bluetooth version 1.4 on Amazon, Another one is wifi based. All says ELM327.

[plus 3 golfer]

It depends on your phone or tablet or PC you plan to use in the car. I have an older IPad just with WiFi and an IPhone with Bluetooth and WiFi. So, I bought the ELM 327 with WiFi. Then you'll need an iOS or Android app to monitor and record data. I have both Engine Link and DashCommand.

 

EngineLink allows custom PID so you can look at Vehicle specific data by entering the appropriate address and formulae. But, the logged data is not in a readily usable form.

 

DashCommand is a more full featured app but does not allow custom PIDs But the log data is in csv file format and easy to manipulate in Excel.

[Bill-N]

As discussed in another thread, there's also TORQUE for android devices.  Basic version is free.

[webcontrol]

I ordered one of those with Bluetooth, hope to use it with my Android tablet.  I almost ordered one with highest review, after digging its reviews I noticed that does not work for Ford vehicles. Ford only uses J1850-PWM protocol.

 

I noticed same thing again this morning. I was driving little slower this time, about 25MPH speed, both ICE and EV motor were on. When stepped on gas, EV motor increased output, gas motor did not.  Then when EV battery indicator running low, ICE increased its output and took over, EV motor stopped.

[plus 3 golfer]

If you ordered an ELM 327 that says it supports all protocols then you are good. But if it only supports J1850-PWM (an older protocol used by Ford) then it won't work. The C-Max does not use this protocol.  The C-Max uses the ISO 15765 CAN protocol (which I thought all manufacturers had to use as of a few years ago).  Look at the pins in the OBDII connector and you will see that pins 2 and 10 (J1850-PWM) are not there but pins 6 and 14 are there (ISO CAN) in the diagrams in this link.  I hope you ordered the right one.

[hybridbear]

Either there is a problem with webcontol's car or he may not really know what he thinks he saw.

This behavior is fairly common. In my observations, it seems to happen more often at colder ambient temps. Our FFH behaves this way quite often in the winter but almost never in summer.

 

I noticed same thing again this morning. I was driving little slower this time, about 25MPH speed, both ICE and EV motor were on. When stepped on gas, EV motor increased output, gas motor did not.  Then when EV battery indicator running low, ICE increased its output and took over, EV motor stopped.

The solution is to shift into L as previously was stated.

[webcontrol]

The sensor I am buying saying also support ISO-15765-4.  Waiting it to be shipped over.

 

Hybridbear, if that is a command behavior, what is the reason behind it?  Does Ford plan to get rid of that behavior?  In my opinion, that's just wasting energy.  To keep shifting gear is not the best way to drive this  fun car.  To save one drop oil here, save little bit of EV battery there, that will result a great fuel efficient car.  In my narrow minded opinion, if user sets EV+ mode to on, this car firmware should only use the max fuel efficiency way to handle ICE and EV.

Edited April 8, 2014 by webcontrol

[hybridbear]

Hybridbear, if that is a command behavior, what is the reason behind it?  Does Ford plan to get rid of that behavior?  In my opinion, that's just wasting energy.  To keep shifting gear is not the best way to drive this  fun car.  To save one drop oil here, save little bit of EV battery there, that will result a great fuel efficient car.  In my narrow minded opinion, if user sets EV+ mode to on, this car firmware should only use the max fuel efficiency way to handle ICE and EV.

I have no idea. The Prius usually behaves this way. The Prius rarely uses the ICE to charge the HVB. It instead runs the ICE a lot more but at a much lower fuel consumption, rates much lower than our cars can go. It also often uses the HVB power to support the ICE since the ICE is small & weak. In the Ford hybrids the ICE is much more powerful and it doesn't need help from the HVB but rather can be used to drive the car and charge the HVB. I've noticed that the Energi in hybrid mode behaves much more like the Prius and almost always uses this mode. The Energi in hybrid mode gets worse fuel economy than the hybrid, not just because of the added weight, but also because of the computer programming.

 

I have no idea why Ford has programmed it this way or how the computer decides to do this mix mode sometimes. It does the mix mode most often on the freeway which is when it is really inefficient because I want the ICE to charge the HVB when it's on so that I can drive stretches with the ICE off in EV mode. Any time spent in this mix mode takes away the opportunity to drive in EV mode.

[fbov]

... I was driving little slower this time, about 25MPH speed, both ICE and EV motor were on. When stepped on gas, EV motor increased output, gas motor did not.  Then when EV battery indicator running low, ICE increased its output and took over, EV motor stopped.

I just re-read the thread to be sure I hadn't missed something... I don't think I've ever seen ICE with EV unless I asked for them both via throttle position. Only when SOC indicator is full does the battery discharge with < 2-bar acceleration.

 

Which brings me to the point; how prevalent is this behavior (ICE + EV until SOC runs out)?

 

Any chance this is a symptom of something like a PCM update gone awry, but not terribly awry like JohnnOhio's first update did. A subtle failure mode that's either hard to detect (like me) or only present on a fraction of the population.

 

Just a thought...

Frank