Any advice for new Hymotion user in cold weather?

Hi all,

I recently purchased a used 2007 Toyota Prius which had the Hymotion L5 pack preinstalled in January 2009. I purchased this car in California and drove it back home to North Dakota. The car averaged 40.1 MPG without the pack charged for the trip home (over the mountains in somewhat cold weather (30-50 degrees)). I would imagine with the pack depleted that my MPGs would be worse (with the extra 200 pounds in back).

Of course, the climate up here can be pretty cold. This week most of the mornings have been anywhere from 10 below to 10 above. I am able to leave in the mornings with a full charge on the L5. I live in a small town where I need to drive probably about a half mile to the highway. For this stretch I am going under 20 mph. During this phase my MPGs are generally 20 or 30. When I get to the highway, I gently accelerate to about 65 or 70 MPH. Once reaching these speeds, my MPGs are usually around 55 overall. I have about 20 miles at this speed until I reach town where I drive about 45 MPH for five miles. Then I have a stretch of about 7 miles at 60 MPH.

Right now, the L5 seems to last about 27 miles. My commute is about 32, where I can plug in and fully recharge. So round trip, the L5 is almost always charged.

Overall my total MPGs since I have been using the pack is only at about 45 MPG. There have been a couple of days where I wasn't able to charge and had to drive back home without the pack charged, so the 45 MPG does include some non-L5 operation. I would say that about 75% of the driving so far has been with the pack charged. Shortly after I purchased I charged it for 2.5 hours and was able to drive 10 miles at 70 mph before it was depleted, but only averaged 47 MPG (it was about 10 degrees with a stiff crosswind though).

I have noted some stretches with over 99.9 MPG....sometimes even around 50 or 55 MPH.

How much effect does using the Climate Control have on the MPGs? Even with the heat running, for some stretches I am still able to get 99.9 MPG, but I would imagine without using the Climate Control, I would be getting much better MPGs.

One thing that is kind of frustrating is not being able to use just electric for short trips under 35 MPH. In town when I drive the MPGs are always low when leaving the garage at home. Even when going downhill without apply the accelerator, I notice MPGs are low...which doesn't seem to make a lot of sense.

At work, I often leave for lunch and travel two miles on roads that are entirely under 35 MPH. Here I noticed for pretty much the entire four mile round-trip that my MPGs are only 20-40 or so.

It almost seems like at lower speeds that my MPGs suffer the most.

I did a test the other day going 30-40 MPH with a charged pack and if I was able to stay at those speeds in cruise control, the MPGs were a lot better.....often over 99.9.

Would there be any benefit installing the EV only mode (like the one coastaltech offers)? Can this even be used with the Hymotion pack? It would be really nice to have a way to use electric only for short stretches under 35 MPH. Should you be able to use EV only mode, even when accelerating as long as you are under 35 MPH or does EV only kick in once maintaining a constant speed?

I have heard conflicting reports of whether you can install the EV mode with the Hymotion or not. Some places I read that the Hymotion always tries to request EV so it is unnecessary. I think I even read somewhere that a customer's EV switch that was already in place had to be removed when the Hymotion system was installed.

I am also a little confused about whether the Hymotion pack can be turned on or off during driving. From the Hymotion manual, it seems like this is highly discouraged. Is there any truth to this?

I have also heard of adjustments to allow 52 MPH in a pure EV mode. Would there be any benefit of this, or would this simply deplete the battery a lot faster?

Does anyone else have experience in cold climates? How much difference would a block heater make?

One other thing I had happen, which I think is a known bug is that my check engine light came on along with the triangular red icon with exclamation point one morning after the car sat overnight in 10 below weather. The car started okay (although it made a loud noise at first), but had the error lights on the whole drive to work. I charged the L5 at work, but when I went home, the car would not start. It required a jump. After jumping, I did the thing where you hit start, wait 30 seconds, hit start again, wait 30 seconds, etc.....this cleared the error. The L5 light was blinking though. I drove it for a while, then turned it off for five minutes and then when driving it again, it was ok. Does Hymotion have a fix for this yet?

I appreciate any input, comments, or suggestions.

Thanks!

 

Thanks for the information....it is appreciated. I will do some checking into this!

 

Thanks for the input. I really think I will do better with an engine block heater. I am hoping that the worst of winter in terms of cold is over for this year, but you never know living where I do.

For the past week, the temps have been around 30 and my MPGs have been a LOT better. On flat stretches of road I can over hit 99.9 for continuous stretches as long as it's not windy; up to 60 MPH.

I've also been keeping my battery off when I leave in the morning until I get up to 70 on the main highway. I'd say right now I'm averaging in the mid 60s MPG when going 70. I have a stretch of about 20 miles going 70....then about 4 miles 45-55...the about 7 miles of 60....for the stretch after I am done going 70, my MPGs skyrocket as expected. Most days I make it to work just as my battery runs out.

Do you have an EV switch on yours with the Hymotion installed? I've heard that with some models that these don't work (I think it depends on when it was made). I would love to have an EV-only option for when I leave my garage to drive a mile away from home and back. A quick trip around town is always a major MPG killer.

 

Do you have to take your car to a location that installs the Hymotion to get the firmware update? I am still a little confused about which versions of Hymotions cause the automatic start of the engine when booting.....is this eliminated with the firmware update?

 

I can vouch for the dramatic hit to MPGs in the cold. It's been really cold here again in North Dakota and my MPGs have dropped 4 MPG over the past couple of days. About a week ago, when it was in the 30s when I would drive around town at 25-30 MPH with a charged battery, I would almost always get 99.9......with the cold again, it is almost always at least half that.

I just ordered a Scan Gauge II and am looking forward to working with that. It should tell me a lot more information when I'm driving that I didn't have previously.

Recently I have not always had the lights off, radio off, heat off, etc, when starting. I'll have to remember to adjust those.

I've only had one incident in the cold where it operated funny. When this happened and all the lights came on, I drove it for seven miles. Then I plugged it in. When I came back a few hours later, everything was drained. I was able to get a jump and drive the car. However, all the lights were still on...check engine....triangle...etc. I looked in the Hymotion manual and followed their advice of hitting the reset button on the pack. Then I shut the car off and on five times waiting 30 seconds in between each. Then all the error codes went away. The Hymotion pack light was still blinking. Then I let the car sit for five minutes. Then it worked again. I have contacted Hymotion to see what I need to do to correct this....sounds like the firmware update I have heard mentioned on here.

Can you buy any engine block heater or do you need a specific one? Believe it or not, I've never owned one before....even living up here....guess been pretty lucky with reliable vehicles.

I do appreciate all your feedback. I look forward to seeing what my MPGs are once summer hits. I've been averaging 60 MPG, give or take a couple....which isn't too disappointing considering I'm just learning to drive with Hymotion and it's been cold out. I think I could probably use a little more air in the tires too....right now they're only at 35 or so....which I know is a little low.

Thanks again for the input!

 

Where can I find/purchase this booster unit?

 

Thanks for your reply. I haven't had a chance to put in a grill block or an EBH yet, but luckily it's been a lot warmer here recently which helps. I hope to do that sometime soon. I just contacted A123 systems and they sent me out an "L5 Booster" unit. I haven't installed it yet, but it should help out.....hopefully we're past the really cold weather this year though....at least I can hope!