My driveway is such that I have to back uphill to get out to the road (See my avatar -- that's Subaru on the left and a Honda Civic on the right) Will TRAC kick in and prevent me from getting out? Rocking forward is not an option normally.
My general experience is that traction control helps, rather than hinders, movement. When one tire spins it applies a brake to the other, allowing power to go to the tire that is not spinning. It also reduces the gas. Thus, at an icy intersection, when other cars are madly spinning their tires and going nowhere, I can floor the accelerator and the car says to itself, "Silly driver, that's too much gas." and gives it just the right amount of gas for the conditions, and my Prius moves ever so slowly (but faster than most of the other cars) through the intersection. But you probably want the best snow tires you can get. You cannot rock the car, but you cannot rock an automatic either.
That sounds as if it will work perfectly for this situation Danny, thanks. I am gonna be getting Michelin X-Ice snows unless something changes my mind by January when I pick up the Prius. CU rates them at the top for traction in ice and snow as far as non-studded tires go and I don't want studs.
Oops --- I still don't know if TRAC works when the car is in reverse? Since there isn't actually a reverse gear and the car uses the electric motor for reverse -- TRAC might not engage?
yep, it works in reverse. Tried it yesterday on 2" of packed snow. punched it and sure enough I had a controlled backing up instead of the spinning tires with no steering control.
Having bogged down on Winnipeg streets last winter during our blizzards - before my winter tires arrived - I will also positively state Trac engages in R. Proper winter tires make all the difference.
"When one tire spins it applies a brake to the other, allowing power to go to the tire that is not spinning." I don't think the Prius TC works this way. It seems to be more of an ICE-cutout than a limited slip diff or electronic braking control. It just cuts power for a second and then retries. My jaded opinion is this is a Microsoft-esque "it's not a bug, it's a feature" kind of marketing effort. They needed to limit wheelspin to protect the PSD, and call it TC to make it sound like a feature. And it's "free"! What a marketing trick!
I believe that because of the way the planetary gear works, TRAC is more important in reverse to prevent overspin of MG1 than in drive.
Just don't try to back up a steep icy slope. My house sits at the end of my very steep and short driveway. As I was backing up this morning in the 1-3 inches of snow, the TRAC engaged and stopped both front wheels from turning. Ok, fine, but there isn't anything else to grip to. Guess what, the car slid back down to the house. I came really close to taking out the garage door... I really wish there was a way to disable the traction control.
Well actually there is and it's posted here. It's called Inspection Mode. http://priuschat.com/index.php?showtopic=6...ion%20mode&st=0 It's on page 2 of this topic but I would suggest reading the whole topic before use use it. I think it would be easy to damage the PSD with TC disabled. I have tried it and it works but I was very careful with the car when I tested it.
Nope. I have the stock OEM tires. I'll bet that I _could_ get better tires but for the two or three days that the weather might be bad... Or, I could just stay at home and not worry about it.
