larryh

Today, after sitting overnight in -15 F temperature, the HVB temperature is down to -2.2 F. The estimated range is down to 15, from 25 in the summer. As always, when it is -15 F, the Intelligent Access Key (IAK) loses its intelligence. In order to start the car, I have to put the IAK in the backup slot. It cannot be used to unlock the doors either. It simply does not work when it is this cold. Has anyone else that has left their car out in -15 F temperature overnight had this problem?

The following shows the Engine Map computed from the OBD II data for the 60 mile commute at 3 F in the previous post #34. I used ICE RPM, % Load, and Fuel Consumption (gallons/minute) data during the trip to compute the chart. The chart is a crude approximation. I don't have enough data to make an accurate map and the data is not all that reliable. For instance, the values of RPM, Load, and fuel consumption are, in general, not synchronized. They are computed at different times. So if I am using data from a time when the ICE is changing RPMs or Load is changing, then the data is suspect. Along the x axis is ICE RPM from 1750 RPM to 2450 RPM. Along the y axis is % Load on the ICE from 65% to 85%. I suspect this is relative load so the chart is distorted. The maximum torque that can be produced by the ICE varies with RPM. This chart assumes it does not vary with RPM. I am using % Load as a proxy for torque. I simply computed efficiency as RPM * Load / fuel consumption. RPM * Load is proportional to power. So the higher the efficiency, the more power the ICE is generating per quantity of fuel consumption. The car was operating at a constant 2075 rpm and a constant 67.7% load when going 65 mph. This is indicated by the black circle on the map. The car did not appear to be running the generator, so there was no additional load on the ICE other than for propelling the car. In order to provide sufficient power to 65 mph, the ICE has to operate somewhere on the black line. It looks to me like it is selected a good efficient operating point. If the RPMs were much lower, then efficiency would decrease, i.e. deeper into the purple colored region or one of the other less efficient colored regions (green, red, or darker blue). Faster RPMs may look more efficient on this chart, but the chart is not all that accurate, so I cannot conclude that it would actually be more accurate to operate at higher RPMs. Adding additional load to the ICE would decrease efficiency (the operating point would move up along the y-axis further into the purple, green, red, or darker blue regions), so that could explain why the ICE is not charging the HVB battery. So I suspect the car is doing what it is supposed to do and run the ICE at its most efficient operating point for the power required.

When running in EV Later mode today on the Freeway at a constant 65 mph, I observed the ICE rpm to be constant at 2075 rpm with a constant 68% load. The SOC of the HVB remained constant. There was very little charging or discharging of the HVB. This was for 10 miles at about 3 F. There were no EV miles for this section of the trip. So it was purely the ICE powering the car during this interval--no plug-in energy was used. The MPG was 37. I think this behavior is different in the summer time, i.e. the SOC of the HVB varies, there are EV miles, and the mileage would be about 44 MPGe. I will have see what happens after the HVB is depleted.

I think you need to specify a temperature setting for the GO time to force preconditioning to make this work for GO times. That would be a big waste of energy. But preconditioning would force the HVB SOC to fall below the level that requires charging. I'm not sure setting a GO without a temperature would force the car to check the HVB SOC. In which case, the GO time would not work to keep the HVB and 12 V battery fully charged.

It does not always charge the 12 V battery when you leave the charger plugged in and select the Update button from MyFord Mobile. I think it only does that if the HVB is not completely charged. It may take a day or two after the HVB has been fully charged before the SOC falls low enough for this to happen. Below is a chart of the power consumption of the 240 V charger after selecting the Update button from MFM this morning. It has been more than a day since it was last charged and the temperature has dropped 30 degrees F since then to -10 F. Initially, it is drawing a few hundred watts to charge the HVB in addition to the 12 V battery. After about 1.5 hours, the power consumption drops to about 70 watts. The car is continuing to charge the 12 V battery. It completes at about 8:20 am. Then for some reason it wakes up a couple of times at 8:40 am and 9:00 am. Shortly after 9:00 am the timer cuts power to the charger. Note that the timer turned on power to the charger at 9:00 pm last night. Since the battery was still fully charged, charging did not start at that time. Because I have the charger on a timer, each time the timer turns on the power, the car checks the SOC of the HVB to determine if it needs charging. So in my case, if I were gone for a long period of time, the car would be continually recharged each time the SOC of the HVB falls below the completely charged threshold.

The snow drift I was stuck in was about 1 foot deep. The tires on the car don't do well in deep snow. When there is more than five inches of snow on my driveway, I have a lot of difficulty geting up my driveway (its a typical driveway with a slight incline up to the garage). I have to make several attempts trying to get up to speed before entering the driveway. But I also had difficulty with previous cars that did not have snow tires, but not as much. The traction control seems to work well on icy roads. I have very little difficulty accelerating away from stop lights, whereas in previous car, the wheels would spin quite a bit. Snow tires would do a much better job on snowy and ice roads than the all season tires that came with the car. See the following video:

I did turn traction control off. That didn't help much. Later, while I was rocking back and forth, I got some notification that I missed on the information display. I couldn't tell what the wheels were doing--I wasn't moving and the car doesn't make much noise. The snow was too deep. I had to get out and shovel. So I turned the car off and on. That seems to have re-enabled traction control. I then was then able to get out.

This is only in the 2014 owners manual. It is not in the 2013 owners manual. So is this a new feature for 2014, or do 2013's also have it?

So because of the slippery road conditions, the tires could not get enough traction to accelerate the car normally. After this happens for a while, the car gets confused and declares that the accelerator sensor is not working properly. It then decides to ignore the accelerator and provide constant steady power to the wheels for you instead. Then you are supposed to control the speed using the brake pedal instead? I wonder if that was what happened when I was trying to dislodge my car from the snow. That certainly isn't very useful "feature" if you are stuck in the snow. They need to warn you that this is happening. Otherwise, people may panic, especially when it is slippery, and cause accidents.

On Saturday, snow had drifted around my car and I had a hard time getting out. I remember some notification or other popping up, but I didn't catch what it was. I'm not sure, but I don't think the car was working quite right. It is very hard to tell what is going on when the engine is not running. I can't tell if the wheels are doing anything. Anyway, I turned the car off and back on again and eventually managed to dislodge the car from the snow. That is when it noticed the communication fault DTC.

I am referring to Ford Service for this forum. I would have to go to my dealer and have them scan the DTCs. But by then, they will probably have been deleted. If the light doesn't stay on, they are probably not all that important. Note that it doesn't always take three driving cycles for the service engine soon light to turn off.

By check engine light, I assume you mean the service engine soon light? That comes on quite frequently for me for various reasons (fuel door is open or a known engine block heater issue) but does not stay on for more than 3 driving cycles. According to Ashley: If you check out p. 154 of the third printing of your owner's manual, it explains the Service Engine Soon light. As long as the light goes off within 3 driving cycles, there's no need to bring it in. If it stays on longer than that, I recommend swinging by your dealer. I have seen mysterious notifications displayed such as "Blindspot System Malfunction" and "Cross Traffic System Fault". The BLIS or Cross Traffic Alert systems are disabled. However, when I turn off the car and turn it back on, everything is normal. This happens only when it is below zero so far. I suspect there is some sort of communication error between the various systems of the car that is not being handled properly or another software bug. You apparently have to "reboot" the entire car to fix these. Hopefully, an important system does not go off line when driving in rush hour traffic. I use an OBD II scanner to look at the DTCs when the Service Engine Soon light is illuminated. I noticed an error the other day that indicated a communication fault. I noted the fault after trying to dislodge the car from the snow that drifted around the car. Ford refuses to support assisting customers with DTCs.

The following graph is for same 8 mile trip as in post 24 above. I have added torque from the ICE to the plot. I am guessing that this shows the amount of force applied directly to the wheels from the ICE. It drops to zero when the ICE is off, and during braking and coasting. It spikes during acceleration. When the ICE is on, the ICE maintains a constant 1500 rpm and a relatively constant load of around 65% (except when stopped, braking, or coasting). While doing that, you can see spikes in the torque applied to the wheels by the ICE. So it appears to be doing a balancing act in the positive split propulsion mode of operation, where power from the ICE is split between the direct path to the road and the path through the generator, to maintain constant rpm and load.

MFT isn't the only system that performs "scheduled maintenance". Last night, the software for the displays on either side of the steering wheel decided to reboot itself while I was driving. The displays simply blanked out and came back in a couple of seconds with the "ready to drive" notification. MyFord Mobile reported incorrect information about the trip. But nothing else was affected.

The HVB voltage is around 340 volts when fully charged. The maximum current I have observed for regenerative braking so far is 115 amps. I'm not sure what it would be if the HVB were at its peak operating temperature rather than in the 40s. Also, I am not exactly sure what the units are on the tick marks for the different displays. But I think they are generally around 10 kW. I received a reply from Ashley regarding them here: http://www.fordfusionenergiforum.com/topic/782-uom-used-for-information-displays/?p=10959.

I received a reply from Ashley regarding the Enlighten, Engage, and Empower screens: The Enlighten, Engage and Empower screens all show different things and use different units of measure, so they can't be directly compared. The lines on the gauge don't correspond to a specific measurement, but rather, represent a portion of the whole -- so if you mash the pedal to the floor, the gauge will max out on the Enlighten screen. As for the difference between the screens: The Enlighten screen focuses on power demand, but only power directly related to acceleration. It isn't going to show use by the climate control or any of that. The Engage screen shows engine power in the white bar, and battery power in the blue bar. This is mostly useful if you're wondering about the balance between the ICE power and battery power. The Empower screen is the one I find most useful. It shows you the power level where the ICE will turn on. By keeping your bar below this indicator, you are keeping the engine from starting. This screen takes into account everything in your car that draws power, not just acceleration.

I believe that the purpose of running the ICE at a constant 1500 rpm is to solely to warm up the engine. The car's primary goal is to still run in EV mode. However, it has to run the ICE intermittently to keep the engine warm. It will run the ICE even if the car is not moving until the coolant heats up to around 110 F. If the ICE has the opportunity to supply some of its power to the generator to provide electricity to the electric motor, then so much the better for efficiency. The electric motor is probably around 95% efficient in powering the car using electricity. The ICE is more efficient at higher loads and lower RPMs. So running the generator and placing a load on the ICE allows the ICE to run more efficiently and the electricity generated is then used efficiently to power the car. It obviously takes more gas, but it generates more power which can be utilized effectively for each quantity of gas consumed up to loads of 65% from the previous graphs. It probably would be better to apply the ICE's power directly to the wheels, but then the car would not have as much control over the RPMs and load placed on the ICE and it would most likely use far more gas than if it only opportunistically runs the generator, contrary to the car's primary goal of trying to run in EV mode and use minimal gas. If you stop at a stop light or decelerate resulting in regen, the load on the ICE is reduced. It does not appear run the generator to charge the battery, probably because the battery is so cold, it takes too much energy to charge the battery for the extra gas that needs to be consumed to generate that electricity. This morning, my 8 mile commute to work at -15 F took 0.05 gallons of gas (with preconditioning of the car). The 8 mile commute home (car sat out in the cold) at -6 F consumed 0.13 gallons of gas. Few cars can match that. Note that the Energi supplies far more than 50 amps of current to the HVB during regenerative braking, up to about 2.5 times that amount.

The Energi also limits HVB power when its cold. This afternoon, after sitting outside in the cold (it only got up to -6 F today), the HVB temperature was 9 F. The Empower display showed the ICE turn on threshold to be 25 kW. It is normally 40 kW. I'm not sure what units each tick mark corresponds to in the FFH, but 25 kW is 2.5 bars on the Energi. The HVB can't generate as much power when the battery is cold. I don't think the MPGe will vary based on the HVB temperature. The reason you get low MPGe when it is cold, is because it takes 30% more energy to propel the car. The rolling resistance of the tires increases significantly, air density is much higher, and the viscosity of the fluids increase causing more friction. See http://www.fordfusionenergiforum.com/topic/1446-cold-weather-observations/?p=10616.

GO times tell the car when it should be fully charged. If you don't set a GO time, there is no guarantee that the car will be charged when you want to leave. It may decide to wait until electricity rates are cheaper which may be after your GO time. For example, if I come home after work and plug the car in, it is going to wait until midnight to start charging. If I set a GO time for 8:00 pm, it will charge sooner to make sure that the car is charged by then, even if it has to charge during peak hours to do it.

Last night when I arrived home, the HVB temperature was 55.4 F and the SOC was 17.8% This morning, when I started to charge it, the HVB temperature was 32 F and the SOC was 11.4%. As the battery cooled, the SOC dropped significantly. I suspect that low SOC shortens the life expectancy of the battery. Maybe that is why Value Charge immediately charges the battery to increase the SOC by 10% if the battery is depleted when it is first plugged in and then waits until the Value Charge time to complete charging. I probably don't want to leave my battery in a low SOC at night waiting to charge in the morning when it is cold.

I updated post #24 above in an attempt to answer these questions. I add the motor and generator inverter temperatures to the plot.