Question about PriusII traction control in winter conditions

Hmmm. Just dreaming I guess. If the main change is in the software, it stands to reason that the software for prior generations could also be revised to improve the traction control's effectiveness. It might not be a simple lift of the GenIII software as there must be some hardware differences. But, if the main advantage is software ... someone, somewhere (even at Toyota) could revise the code for updating prior generations.


>>>The new Prius has an improved traction control system that fundamentally operates in the same way as the previous mode. However, the point at which it engages has been altered (a change in the software for the control). This now allows a very small amount of wheel spin prior to the traction control cutting in and so improves traction of the front driving wheels in slippery conditions, enabling the vehicle to have more overall grip and improving the "feel" for the driver.<<<

 

The issue of Prius Gen 2 traction control ("TC") in snow has been discussed a lot, so you could do a search, but here is my take.

The TC is designed to reduce/cut power if the front wheels are spinning. A very small minority of Prius Gen 2 owners complain about the TC in very slick/icy conditions. They claim their front tires can't get grip, thus try to spin, and the TC cuts off power, so the car is supposedly immobilized.

After reading lots of those threads, I've noticed that most of those Priuses seem to be equipped with the stock tires. The Integrity tires are reputed to be awful in snow. I can't recall hearing this complaint from anyone who had good all-weather tires or snow tires on their Prius.

Also, this complaint is mostly heard about the earlier Gen 2 Prius. Somewhere pretty early in Gen 2 (2005? not sure) the traction control settings were tweaked to allow a little wheelspin. My 2007 has the revised settings, as do most Gen 2's.

My own experience: 2007 Prius, live in Oregon, every winter we take multiple trips to see family in Eastern Washington where it is snowy and icy, plus occasionally we'll have snow locally (like last year). We put Blizzak snow tires on the car from November through April.

With those tires, the Prius is quite a good snow/ice car, never any problem getting moving on ice or slick snow. I had a good time playing on a parking lot covered with glare ice: floor throttle and the car pulls smoothly ahead, try running on that surface and you'd fall. It will also climb a relatively steep driveway even if the surface is iced-over. The car will pull itself through at least 8" snow without any fuss, whether the snow is fresh, packed, slushy, dry, etc. I have not tried anything deeper, since the ground clearance is limited. Again, that is with snow tires, I have no experience driving on the Integrity tires in the snow.

As for other slippery conditions like rain, loose sand, etc, using the Integrity tires, in some cases I can get TC to kick in if I pull away from a stop using heavy throttle, the car accelerates rather jerkily for the first 20-30 feet or so before reaching a speed where even heavy throttle doesn't threaten wheelspin. Or, I can pull away using my usual moderate throttle, and TC never kicks in.

Bottom line, I've never been immobilized or hampered in any way by the TC. I'd say it is no issue unless you (1) have a early Gen 2, (2) the stock Integrity tires, and (3) are driving on ice or very slick snow. Combining (2) and (3) is a bad idea anyway.

 

Hi...

I agree with most things written above. The most common "problem" with Gen 2 owners in winter was their poor choice of tires.

I leave in northern Quebec more precisely in Saguenay. You already know that here the winter are pretty severe and that winter tires are mandatory anyway.

On my 2005 with good winter tires (Blizzak, Nokkian or similar), I have no problem at all in winter compared to any other fwd cars. Even with my "spirited" driving, even with all the hills around here.

So if you get the Gen 3 with good winter tires and the revised TRAC system, it should be great all winter long :rockon:

 

If the GenIII Prius applies a brake to the spinning tire, that is welcome news. The previous Prius Trac did NOT do that.

With my 2004, I've encountered frozen edges on streets once the Spring melt occurred, after it was time to remove the studded tires. With studded tires on, I had little problem with one drive wheel on pavement, the other drive wheel on ice

With the Michelin Harmony tires back on, the Prius would barely move when the light turned green. If the brake really was applied to a spinning wheel, my Prius would have been able to easily drive away

I have another vehicle as a ready comparison, my 2007 FJ Cruiser. The Trac in my FJ actually does apply the brake to a spinning rear tire. Without the winter tires on, in 2H, if one rear wheel is on ice, and the other rear wheel is on pavement, the electric brake booster starts rattling, and the FJ is easily able to pull away

I did test drive a 2008 Prius when there was still a bit of snow around. The Trac behavior was day and night different, compared to my 2004: much improved