it would be interesting to plug a scantool into a car that was doing that... hmm. if i ever see conditions where my car does that, i'll see if we can set that up.
I've noticed this twice in the last couple weeks. Both times the battery was at 8 bars (never saw that before), the ICE cycled about 8 to 10 times and the outside temp was in the teens (F). I first thought it was trying to get more heat into the system and the high SOC of the battery would rapidly shut the ICE back down. After reading this thread, the earlier explainations make more sense. The reassuring thing is that this is normal
interesting thread... its great how questions can bring so much valuable peripheral knowledge to the table. as i have never experienced the situation described, cant really comment on it. although, in winter i can turn on the ICE at will by simply turning on the defrost. being in a temperate climate, i also subscribe to the 65º is too hot faction so cycling the defrost on and off or to heat is a common thing for me. defrost uses a lot more power than heat on the same settings especailly after the car is warmed up but even when toggling the defrost on and off, i might be lucky to go through 5-6 startup cycles per minute. my SOC range is very small, runs from about 55-65% and frequently i take trips where the entire range is much smaller than that. it makes sense that the SOC would be maintained at a slightly higher level in colder weather, but i have not seen any real evidence of that so far. **edit** i also believe that when the ICE spins, it does burn gas most of the times. being winter, its not easy to come even close to fully charging the battery so will have to revisit this question, but i do know that i burn gas when at 99.9 mpg on long downhills. i previously thought i wasnt but SCANVIEW tells me different. sure i average as much as 200-250 mpg.. but still using something. but have yet to see a situation when the ICE is spinning without any gas consumption
Ok guys, I further asked Wayne to speculate as to why he thought Robin's Prius might have gone through the protracted cycling period like it did. And BOY did he send me a response. Warning, this is some relatively dense stuff on battery function, but as far as I'm able to understand this stuff it makes sense. And, btw, the short answer is that it is routine battery maintainence.
Very nice description! It would be interesting to hear Wayne's take on the EV button in relation to SOC maintenance on the battery. From the write-up, it sounds like we may be stressing the battery a bit...
I can assure you he has no concerns. He's the first one in the US to install an EV button and is the one that told me how to do it which allowed my original write up...I was one of the first 5. He still uses his. I don't think he feels it interfers with the battery or creates undue stress. That said, he's also added and removed and re-added additional batteries and such.
Here's the story leading up to my Prius going on off on off This was the summer before last in the 80s went into town 12 miles one way. Pressure washed the car at the car wash Ran fine all the way home got to my steep driveway went halfway down Prius at a noise down position sat there minute or so for the cat to move ( cat is 17 years old moves Very slow) and that is when it started BARS where Blue.I think it was a glitch maybe the water went somewhere it shouldn't have.
so that stuff that evan posted was WAY over MY head... i had my husband take a look through it since he's the wrench turner. he has this to say: a. thanks to evan for sharing this! b. thanks to wayne for sharing his wisdom too. that was amazing. c. it makes perfect, brilliant sense. WOW. d. there is NO reference to any of this in any of the prius tech training materials that he has seen. e. he is very happy and excited to have someone explain this to him. f. it will be printed and shared with all the prius techs at work so they can better answer their customers' questions rather than telling them 'no, there's nothing wrong with the car, sir' so overall, a big thank you for that. it's just another reason we really enjoy this forum.
Heck, here they are for the currious... Patent #6600293 Patent App #20050083017 Patent App #20030025479
its threads like this one that really has me missing the ability to create faves like the old forum... gee what i give up just for speed and reliability
I have the ScanGage and though it is not the Toyota scan tool it does show RPM, Gallons/Hour, and Engine Temps. I forced the issue this morning and drove the car to the big hill going into down town Olympia. Got the car well charged and let it cool off at the top of the hill. Coming from the east this is a long hill with a 25 mph speed limit. I hit every light going down hill and was at 138 and 8 green bars at the bottom of the hill and it cycled as described 8 times before the light changed at the bottom of the hill. The ScanGage reported that the car was using gas. Now that is FWIW. I am still not entirely sure that the Gallons/Hour is totally accurate and there are clearly sampling rate issues with the ScanGage. BTW I concur on putting the battery maintenance paper in the knowledge base.
Thank you for the good answer, I was always interested in following the rules with the cars battery warranty so I never considered an EV button. Which EV would your husband recommend costal or factory? Also can the knowlege of battery needs be used to helped out the prius battery by useing the Ev button to discharge the battery before going down large hills? I think that everyone on this forum would like to use the ev button to help maintain battery effectiveness. Again thank you for your help. My wife and I are buying another Prius in January and you can't imagine how much a good answer means to us. We were thinking we were making a mistake to buy another Prius without this on off on off question put to rest. thank you and Merry Christmas.