For those of you with more experience with the Hymotion pack than I: 1) What does it mean when the car "chirps?" It seems like I get 3 or 4 chirps on occasion, with each chirp itself being a rapid succession of 3 individual chirps? I assume it is something to do with the Hymotion pack because I never heard them before the pack was installed. 2) Under light acceleration, say 1 mph/sec, when the engine is just barely contributing to acceleration, at around 31mph (+/-) the engine stops putting out power (the arrows from the engine disappear), the car noticeably hesitates when the engine drops out, I get 3 or 4 chirps, then the engine comes back "online" about a second or two later and all is well. Under normal (i.e. faster) rates of acceleration, this does not happen. Is this a Hymotion quirk of some sort that anyone else has noticed?
1) Sounds like the Hymotion is trying to enter EV mode and the car is denying it for some reason. Could be because your above 34MPH or because the Prius battery is too cold as some examples. 2) I dont know why the car will chirp in these conditions or if the Hymotion battery is sending the chirp signal. If it only does this on occasion then there must be some condition the Prius wants to exit EV mode. If it does it every time I have no clue. I really cant comment on how the Hymotion battery uses EV mode as I have mine disabled and I use a manual EV button. Like mrbig said get in contact with Hymotion. With all most 3 years of being available to the public they should know all the little issues by now.
Good luck with that. I have tried to contact them before and had no reply. The behavior you are describing is exactly the way the Hymotion kit works in my car too. You start accelerating gently, the engine is on (although you might not even see any power coming from it), you get to 34 mph, and suddenly the signal from the Prius that you cannot go into EV mode, the engine cuts off, goes to EV mode for the one second that you're at 34 mph, then comes on again. That has been the most annoying part of the conversion. Now, if you're accelerating absolutely at a snail's pace, or going downhill in glide, you can go through the 34 mph barrier without having the engine come on.
Yeah, they are not very responsive. I am going to try to send them another email shortly then I will give up. If yours is doing the same thing I guess it could be a Hymotion thing. When my garage warms up this spring I am going to install the Coastal switch and see if that works...
I would suggest that you consider looking on eBay for the correct Prius switch assembly. At the right price, it might not be much more than the Costal switch, and you can take a few months to look.
I already bought the coastal switch. I thought the coastal switch was a descent alternative to the more difficult to install switch you are referring to?
I started thinking that there are a couple more "quirks" that I'm wondering if anybody else is seeing. I get the Hymotion kit to start off in EV only by starting the car with the kit off, shifting to N, then starting the Hymotion, then driving. When I get the Prius to start the warmup, either by going over 32 mph or shifting into R when stopped, if I'm in D it does not show the running engine charging the hybrid battery, but if I shift into P it does. So what I'm wondering is if I'm in D, is it still charging the Prius hybrid battery and not showing on the screen, or is it just not charging unless you're in P? Also, is there any way to break the Hymotion control when it won't let you go to the Climate screen to turn the fan on?
I still think when stopped the prius charges the battery during its warmup. I could be wrong. I never pay attention to it. The only way to stop the screen from flippipng is to turn off the hymotion battery and then you can change your settings. This is very annoying if you have navigation and need to use it.
I am able to access the climate screen freely with the Hymotion system on. Sometimes Hymotion will "steal" the screen away from me like it does with the NAV screen, but I can reselect it no problem. I've noticed the traction battery charging thing too. When I'm in park, it shows the engine charging the traction battery. When I'm driving at low speed during engine warmup (like I just did today) it just shows the Hymotion system driving the wheels and no arrows from the engine.
I get what i think are similar "chirps" except mine are always three sets of 3 "chirps". I don't notice anything different on the screen, but I have not played close attention. I will now and call the installer in West Palm. Thanks for the info. Best Hal
I called around 2:20pm Eastern and asked to speak to Jon Ortiz. All I could do was leave a voice mail. So We will see. One other unnerving factor is that you see very little mention of Hymotion on their website. Last year at this time one could not avoid the mention of Hymotion no matter where you went on the web page. Coincidence, hopefully....but if it walks like a duck.....an nauseum. Best Hal
I have the same issue with my Hymotion. I asked my installer in Colorado why it happens and was told it was an issue with the Prius system, not Hymotion, but I don't buy that. It seems clear it's related to Hymotion trying to override the Prius EV mode. I was also told that the only thing that could be done was to isolate the speaker which makes the "chirps" and disable it (anyone done that?). Seems like an unfortunate incompatibility between Hymotion and Prius systems--maybe Hymotion will come out with a software upgrade at some point. Discouraging to hear A123 is not responsive to questions.
I called the service manager directly and he told me to bring the car in on Monday the 11th and he would scan. Best Hal
Of course, you can bring it in, and it is great that Jonathan and Foreign Affairs Auto are nice enough to check it, but there really is nothing wrong as far as anything that can be fixed. I think Colorado Carl summed it up, "an unfortunate incompatibility between Hymotion and the Prius systems." You can avoid this if you are able to accelerate extremely gently, getting some momentum up to about 31 mph, then ever so slightly accelerating from there to 35 mph, where you can resume a more normal all-electric acceleration. However, if the car has not had the warmup, and entered S4 mode, you will still get the chirping, but not the jerking.
