Prius Shuts Down In Snow

Ah, consumeraffairs.com. The site that brought us "prius goes on highway rampage."

It's a pretty scummy site actually. They troll for lawsuits. Traction control has been discussed in numerous threads on this site (search "traction") and has not been an issue for most of us.

 

Well, I will agree the "traction" control is my least liked feature on my Prius. Running studded Goodyear Nordic winter tires, it's much less of an issue now.

However when I was out at the hobby farm over xmas and we had the raging blizzard Dec 31, I did manage to bog down. Once you bog down, the wheels refuse to turn, so I couldn't even rock the damn thing. A neighbor came to my rescue, he was driving his wife's 2003 Ford Focus wagon, running the same studded Goodyear Nordic tires. He had no trouble. A bit of pushing and I was able to move again.

The same can be said for the heater performance. Unless you use a winter front, in temps of -30 C and colder, you freeze in the car. I would have expected a lot more cold weather research and testing.

But when you consider there are probably more Prius cars in San Francisco than all of Canada, I guess we shouldn't be surprised.

 

I say again, try and drive a RWD car up that 8-10 degree grade, traction control or no traction control. No way that would happen. all vehicles behave differently in the snow, a limitation is not a safety concern.

 

Perhaps consumer affairs.com will retract/edit their post with a comment like, 'Prius, like any car on ice, trying to go up incline, can't always make it ... unless your car is properly equiped with tire cables or snow tires' ... after all this wouldn't be their first corection, by far.

 

<div class='quotetop'>QUOTE(hill @ Feb 3 2007, 11:11 AM) [snapback]384846[/snapback]</div>

I doubt they have ever issued a correction for anything.

Are you sure you aren't confusing them with Consumer Reports?

They are NOT the same thing.

 

<div class='quotetop'>QUOTE(SW03ES @ Feb 3 2007, 10:32 AM) [snapback]384836[/snapback]</div>

As I have previously posted, TC has kicked in several times on my '05 while I was trying to get up a loosely packed gravel driveway (summer) with hardly any pitch.

I don't know much about the consumeraffairs website but I am in complete agreement with the problem as described. It's my hope that the trolling lawyers will pick up on the TC fiasco and run with it.

 

<div class='quotetop'>QUOTE(Tempus @ Feb 3 2007, 11:45 AM) [snapback]384854[/snapback]</div>

Linky

Like ConsumerAffairs.com or not this is a legitimate complaint that has received more than it's fair share of discussion on this board.

 

<div class='quotetop'>QUOTE(Bohous @ Feb 3 2007, 12:11 PM) [snapback]384870[/snapback]</div>

I've entered my experience with TC on the consumeraffairs.com website with a reference to to the existing article. I would strongly urge those who share my feelings about the downside and possible hazard posed by TC would do the same.

 

Try going slower, down to 1 MPH. The Prius engine cannot stall.

 

<div class='quotetop'>QUOTE(popoff @ Feb 3 2007, 01:10 PM) [snapback]384869[/snapback]</div>

Popoff, have you implemented the fix posted here on PC? We've never had an issue, yet acknowledge some have. That being said, we've disconected the rear sensors ... just in case. Have you?

 

<div class='quotetop'>QUOTE(richard schumacher @ Feb 3 2007, 12:43 PM) [snapback]384886[/snapback]</div>

Thanks, I wondered about that. I'll give it a whirl.

<div class='quotetop'>QUOTE(hill @ Feb 3 2007, 12:45 PM) [snapback]384888[/snapback]</div>

I think I know of the fix you speak of. My concern is it would throw a code and possibly mess up my warranty.

If I read Brian's recent post about Dyno testing his Prius, he mentioned that the red triangle stays on for about 50 miles after he reconnects the sensors. I'll doublecheck his post to see if I've got it right.

Thanks for acknowledging that some have had this problem.

 

<div class='quotetop'>QUOTE(SW03ES @ Feb 3 2007, 11:32 AM) [snapback]384836[/snapback]</div>

My parents didn't buy their first new car until they retired. Up to that point, they kept old cars until the floor panel rotted away, though mechanically they still ran perfectly. My Dad was a good mechanic

As a kid in Utah, I remember our Ford Galaxy 500. Dad put in a Detroit Locker soon after buying it, and for winter would always put on four studded snow tires. He also put 4-6 sandbags in the huge trunk, along with tire chains if needed. I only remember us having to chain up once, and everything else was stuck too. Otherwise it was a tank on ice and snow, no problems going up grades.

It's not so much the Prius having trouble with a 8-10 degree grade, the "traction" control will stop it on LEVEL GROUND. As an extreme example:

The very first winter with the car, my snow tires were backordered until December. December of 2004 and January of 2005 was nasty, blizzards and bitter cold. It was common to find intersections with the sides glare ice, and the center bare.

Now, if the Prius had a "real" traction control - the kind that not only limited power output but also applied a brake to the spinning wheel - I would have been able to accelerate once the light turned green. Instead the icon on the dash was blinking and I was motionless, with cars behind honking at me.

After trying the Dunlop Graspic DS 2 and Yokohama Ice Guard 10 studless tire, both were light years better on snow and especially ice compared to my regular Michelin Harmony tires. However, most other cars could still pull away from me at a green light, and on polished ice I still had problems.

I noticed in October Canadian Tire carrying a European brand of winter tire, what they called the Goodyear Nordic. In the EU it's called the Goodyear Ultra Grip 500, and it accepts studs. I've sung the praises of this tire to friends and co-workers, and a few have purchased them as a result.

http://eu.goodyear.com/home_en/tires/repos...p?page=benefits

Despite the fact they're terribly noisy on dry pavement, I finally have a car that will have no problems and is quite confident on snow and especially ice. Just not deep snow. As I stated previously, during our Dec 31 blizzard, I got bogged down at my hobby farm.

I called for help and one of my neighbors came to my rescue in his wife's 2003 Ford Focus wagon. Now to my eye, the Focus wagon has similar weight and ground clearance to my Prius. If I'm wrong please correct me. He had NO TROUBLE doing a three point turn in the same deep snow I was stuck in.

After some pushing and shoving, I managed to get going again. But the neighbor didn't even have to rock his Focus, just lightly engaged the clutch and away he went, churning through the snow.

It is my personal opinion that Toyota could have done a much better job implementing their "traction" control, or at least to have done "real" cold weather testing in a place like International Falls MN or Thompson, Manitoba. But I doubt they will, since as I stated earlier, there are probably more Prius cars in a San Francisco suburb than all of Canada.

The winter traction issue alone - due to how remote my hobby farm is, right at the end of a 4.5 km long gravel sideroad - has me seriously considering a second vehicle. I've test drove a Subaru Outback 3.0 R Premiere, which has VDC with ETC. It works by applying a brake to the spinning wheel, the way it should work.

I refuse to get involved with "hacking" my Prius by disabling speed sensors, risking catastrophic damage to the PSD. It's just not worth it. It also wouldn't make any sense to rent something like a pickup or an SUV, as they will have "all season" tires and be much less safe on ice than my Prius with studded winter tires.

As a final point, I would hope this forum allows us to discuss our Prius cars, warts and all. If a forum member isn't allowed to bring up a concern about winter driving, then perhaps we are no better than the redneck knuckle-draggers who inhabit the GM Trucks forum.

 

I am going to take the liberty of copying in a summary of a prior thread below, focusiing on the TRAC issue.

The main point is that there is a software error in 2004 through mid-2005 production that can be corrected wtih a reflash. The ones that just stop dead, that's the likely problem. Properly functioning Prii will "pulse" the drivetrain in that situation (repeatedly spin then stop the wheels), not stop dead.. Go get the car fixed is the answer to that.

Otherwise, AT YOUR OWN RISK, you can turn off TRAC, from the drivers' seat, any time you want to.

You can acces the full thread here:
http://priuschat.com/index.php?showtopic=28639&st=80

My summary of the prior thread is below:

-----------

Barring that I'll concisely summarize the TRAC issue and solutions as I understand them. All credit to the original posters.

1a) Some 2004 and early 2005 Prii have an outright flaw in TRAC operation that results in no movement after TRAC is triggered once. Reflash for the known highway stall issue appears to solve this problem.

1b) Otherwise, if the traction is poor enough, attempted acceleration on ice or snow may result in successive cycles of wheel spin and TRAC intervention to stop the wheels, several times a second. I'd say TRAC "pulses" the drive train.

1c) One poster suggests that the best strategy, to keep moving, is to floor the gas pedal when TRAC intervenes in that type of situation. Other suggestions were typical winter car suggestions (snow tires, traction aids, keep momentum up, don't get stuck in the first place, and so on.)

2) There are at least two ways to disable TRAC. Both of them risk destroying the HSD.
2a) Pull the wires off the rear wheel speed sensors (or permanently put them on a switch). This disables TRAC but otherwise lets the car operate normally. Error lights will show on dash. Plug the wires back in, and within 20 miles the car will return to normal operation.
2b) Engage "inspection mode" as described earlier in this post. This disables TRAC and forces the ICE to run constantly. Flashing red icon will show on MFD. Turn the car off and restart to return to normal operation.

3) Earlier threads on this and other boards have flogged Toyota over the TRAC issue in the Prius. They also raised the issue of having limited wheel spin instead of zero wheel spin as a TRAC setup. Years ago.
3a) I infer from that that Toyota either can't or won't change the TRAC setup to allow limited continuous wheel spin. They certainly know by now that it bugs people.
3b) That means the "starting from a gravel patch" TRAC issue, at this time, appears an inherent problem with the Prius. Unless you a) want to modify the car to cut out the rear wheel sensors as described earlier in this thread, and b) have the presence of mind to turn it off ahead of time. There is no automatic fix.
3c) But the "I'm stuck in 2 inches of snow" issue may be at least partially addressed by turning off TRAC once you are stuck. With completely understanding that doing so may destroy the HSD. I printed the complete directions for turning off TRAC and stuck them in the glovebox with the manual.

4) I had some trouble getting this to work. You have 60 seconds to perform the sequence, from the time you press the start (power) button. For the record, as clearly as I can put it, to turn off TRAC:
a) Begin with the car off.
b) Keep your foot off the brake, press start (power), wait for MFD to come up.
c) Keep your foot off the brake, press start (power) again, wait for dash warning lights to come up.
d) Press the gas pedal to the floor twice while in Park.
e) With foot on brake, shift to Neutral. Verify by looking at shifter symbol on dash. (I have to jog the shifter toward D to get it to go into N.) Press gas pedal twice to the floor whjle in Neutral.
f) Put in park, press gas pedal twice to the floor while in Park.
g) Flashing red icon should appear on MFD.
h) Put foot on brake, press start (power) to start the car.
i) ICE will run constantly in this mode.
j) Drive gently. YOU CAN DESTROY THE HSD BY RUNNING WITH TRAC DISABLED.
k) When done, turn off and restart the car to put TRAC back into normal mode.

Some threads also seem to indicate that you have to let the car go through the normal warmup sequence first, or that the engine can't be running when you do this. I don't know whether that's oriented toward the real use of this mode (for emissions inspections), or whether those conditions would actually prevent you from entering "inspection mode" as above.

Use at your own risk. Every knowledgeable poster has said this is dangerous and could destroy the HSD. I accept no liability in repeating these instructions. They have been posted on this and other boards.

 

my driveway is very steep and i had to make a run at it to get up it when we had snow. tried it a few times and said heck with it, not that important.

well also had to take my Ford F-150 up it and when it started to slip i thought for sure i was going over the side (my drive is about 7 feet wide drop off the low side, brick wall on the high side and it tilts slightly to allow drainage...) my drive is very narrow and has a 3-4" border that saved me from rolling it into my neighbors yard. after the blood returned to my brain, i slowly back that sucker back to the bottom of the hill, and parked in the upper parking lot.

so imm, not having traction control is a major safety issue.

 

<div class='quotetop'>QUOTE(chogan @ Feb 3 2007, 09:24 PM) [snapback]384980[/snapback]</div>

I asked my dealer about this issue last fall and again just on Friday - apparently my Prius has the corrected software.

To reiterate: I don't have a problem now on ice or in moderate snow. I can probably thank my new studded snow tires for that. If anything I can easily dust an SUV or pickup, especialy on ice.

It was the blizzard on Dec 31 when I bogged down. The car would initially strain, then nothing, with the Trac/VSC icon flashing.

True enough it was around two feet of snow. I should have taken the Ford F-150 I have at the hobby farm, in winter I run studded Cooper Discoverer M+S tires. The truck has a Detroit Locker in the front axle and a PowerTrax LockRite in the rear axle. With 600 lbs in the box, I can leave the front hubs in Free and handle two feet of snow no trouble.

But when a neighbor with a 2003 Ford Focus wagon - running Goodyear Nordic studded tires - had no trouble, methinks this car is less than suited for severe snow events.

Look, we've also had forum members with 2006 and 2007 Prius comment on this. I certainly don't intend on getting rid of my Prius, it's just that for the 180 km trip out to my hobby farm I should perhaps rethink what vehicle to use.

It's all blacktop except the very last 4.5 km, when I turn off the highway and drive down a winding washboardy gravel sideroad. My hobby farm is right at the very end of that road. I can usually expect good road conditions, except for winter snow and summer washboardy conditions.

I'm already stuck with a second vehicle anyway, my Dad's 2003 Buick LeSabre. He doesn't drive anymore, and since my Mom died a bit over a year ago, I only use it once a month or so.

That's why I'm thinking of a 2007 Subaru Outback 3.0 R Premiere Edition, which includes VDC/ETC. With studded tires that car could probably handle any weather my ancient Ford truck could.

In my personal opinion, it simply isn't worth grenading the PSD by disabling the Trac. If Toyota had done a bit more homework, they could have added a software defeat on the MFD, perhaps to limit wheelspin to 10 MPH or so, with chimes and flashing lights to warn you that you were pushing the limits of the PSD.

 

<div class='quotetop'>QUOTE(DaveinOlyWA @ Feb 3 2007, 11:30 PM) [snapback]385008[/snapback]</div>

I believe I've already stated this in previous threads, but imho an empty pickup truck/SUV with open differentials is worse than useless, it's *dangerous.* Especially a 4x4, it gives you just enough traction for acceleration to make a fool think he can stop and *steer* as well. No you can't.

My '84 F-150, I put a Detroit Locker in the front axle. I had ordered it with a TracLok in the rear 8.8 axle, but that was worthless. Never use a clutchpack in a pickup, they suck unless you use such strong bias springs it constantly chatters. I got a new "open" case with regular side/spider gears in the late 90's, and in '02 or so I put in a PowerTrax LockRite.

With at least 500 lbs in the bed, that truck is *very* stable in snow and on ice with the studded Cooper Discoverer M+S winter tires. It's just way too primative for me to drive daily: it has a four barrel aftermarket carb with hand choke, the only "power" is power steering and brakes, no A/C, etc. Oh and try 12 mpg with a tailwind and coasting downhill.

And with that locking rear end, every time you make a sharp turn at low speed you hear it ratcheting CLICKCLICKCLICKCLICKCLICK as the outer wheel overruns the toothed gear. Nope that would make me nuttier than I am right now, and we can't have that.

 

Lots of half-truths or mis-information in your post.

<div class='quotetop'>QUOTE(HiWheel @ Feb 3 2007, 06:52 AM) [snapback]384812[/snapback]</div>

Haven't seen any of what you describe, although
1) you could be triggering TRAC which would last about one second
2) haven't seen or heard of anyone having this problem
3) listed in the manual only if you leave your keys near the car with keyless entry active. (takes some effort)

<div class='quotetop'>QUOTE(HiWheel @ Feb 3 2007, 06:52 AM) [snapback]384812[/snapback]</div>

True. All the power "stops" for about a second, then restarts as a result of the TRAC. It's too sensitive in most people's opinions. It does not, however, STAY stopped, although you don't say so.

<div class='quotetop'>QUOTE(HiWheel @ Feb 3 2007, 06:52 AM) [snapback]384812[/snapback]</div>

Sounds like both the user and the dealer are on drugs. It's clear you've not done any homework on the Prius, but here's a good place to start

http://www.toyota.co.jp/en/tech/environmen...lReports_12.pdf

Page 17 will tell you exactly how the Prius is supposed to behave on an incline with slip. If the dealer or user didn't know this, what can I say. It's how mine behaves, and I've passed people who didn't know how to drive their 4wd up a snowy hill in my supposedly impotent Prius.

<div class='quotetop'>QUOTE(HiWheel @ Feb 3 2007, 06:52 AM) [snapback]384812[/snapback]</div>

I'd be willing to bet you 50$ that context was not preserved here, unless you expect me to believe that Kwon was responding to Christopher's strange cable-chain-slipping situation.

I challenge you to put cable chains on any car with "ordinary" horsepower and get them to "slip" in snow.

<div class='quotetop'>QUOTE(HiWheel @ Feb 3 2007, 06:52 AM) [snapback]384812[/snapback]</div>

Interesting, I do this on a regular basis without losing traction. TRAC does modulate the drive to each wheel if there is slip, but it does this on a one-second interval (or less) such that the car still accelerates.

<div class='quotetop'>QUOTE(HiWheel @ Feb 3 2007, 06:52 AM) [snapback]384812[/snapback]</div>

My car certainly doesn't behave in the manner you describe.

My conclusion: You're a troller from GM.

 

I also agree with the consumeraffairs report. We have a 2004 Prius with brandnew Blizzak WS-50 snow tires mounted on steel rims in the stock OEM size. Although Minnesota is known for some harsh winters, this winter has been surprisingly mild. Needless to say, I was quite excited to try out our Prius with Blizzaks once we finally got a healthy dose of snow in southeastern MN. To my shock and horror, the abysmal traction control spoiled my day and made for a really dangerous situation.

Our last heavy snowfall was about 10 inches or so. The roads in our subdivision were not plowed and I thought this would be a great maiden voyage for the Blizzaks. My wife, two daughters, and I all piled into the Prius early that morning and headed off to daycare. Sure enough, the Blizzaks were downright impressive in the 10" of unpacked fluffy snow in our subdivision. The tires did not slip at all and confidently chewed through like the roads were dry. The blizzaks were performing as advertised.

So far so good, right? Here's where it gets interesting. After dropping our kids off at daycare, my wife and I headed to work and were leaving the daycare's parking lot. We were trying to make a right turn out of the parking lot onto Broadway, a very busy street in the morning rush hour where people travel 50 MPH. The snowplows had already cleared Broadway and dumped the snow into the parking lots exit. This wasn't the nice fluffy snow we experienced early that morning. This was a very heavy, mashed up, salt and sanded, slippery mush that was 12" high and 8 feet into the exit. With my confidence high, I proceeded into the snowy mush, stopped, and then waited for an openning in the traffic. I saw an openning and tried to go. Nothing... The traction control sensed slippage and instantly stopped BOTH wheels completely. I layed off the gas and sat there shocked. What's going on??? I tried flooring the gas for a minute, and could feel the wheels moving very slightly with no movement forward. Ugh...

I ended up backing up out of the mush and waited again for the next open window in the traffic. When the window came, I had roughly 10 seconds before 40 or 50 cars would be right on my tail. With my heart pounding, I floored it. The Blizzaks dug in and the Prius launched into the 8 feet of mush with some good velocity. With about 2 feet to go before hitting clear pavement on broadway, the Prius bogged down... again! With all those cars barreling down at 50 MPH, I felt like a sitting duck in my little Prius struggling to claw through the remaining 2 feet. The traction control was doing it's best to keep me for going anywhere. Ack... Fortunately, I had enough momentum still to finally make it!

I have had cars with traction control before and it is NOT supposed to work like this. Torque is supposed to be diverted to the wheel with grip. If both wheels don't have grip, then the torque should be distributed 50% to both wheels! The Blizzak WS-50s, with their insanely deep 15/32" of tread depth, could of easily chewed through the mush if the wheels were actually spinning. The Prius traction control just never gave them a chance to do their job.

I am very disappointed in our 2004 Prius ability in snowstorm conditions. I have read the posts about disabling the traction control completely, but the potential damage to the drivetrain sounds too risky.

 

<div class='quotetop'>QUOTE(automatic1stdown @ Feb 4 2007, 12:39 AM) [snapback]385047[/snapback]</div>

The exact same thing happened to me a couple of weeks ago. It's frightening to see cars barreling down on me while being stuck in a couple of inches of snow with a dead Prius.

As to the post just before yours, I'm happy for him that his car doesn't behave in the manner described by Mr. "Christopher." Mine behaves exactly as he (Christopher) describes. Does that make me and automatic1stdown (hope you don't mind my including you) trolls from GM? I don't think so.