[debi]

We have a 2005 Prius and experienced a strange situation last weekend and got no good explanation from the dealer:

We stopped on a fairly steep gravel road. When we tried to start up the hill again, the wheels slipped a little, and the "slippery road" light flashed on the dashboard. But the car would not move! It wasn't that the wheels were spinning gravel, I could floor the accelerator and the car wouldn't do anything. We had to back down to road to start again. I tried this again later with the same result. The dealer told me that I might want to call the Toyota customer relations line but I didn't want to.

Any ideas of whether this is a design fault or just a service problem?

 

[efusco]

We have a 2005 Prius and experienced a strange situation last weekend and got no good explanation from the dealer:

We stopped on a fairly steep gravel road. When we tried to start up the hill again, the wheels slipped a little, and the "slippery road" light flashed on the dashboard. But the car would not move! It wasn't that the wheels were spinning gravel, I could floor the accelerator and the car wouldn't do anything. We had to back down to road to start again. I tried this again later with the same result. The dealer told me that I might want to call the Toyota customer relations line but I didn't want to.

Any ideas of whether this is a design fault or just a service problem?

Prius has a very aggressive traction Control (TRAC) that will stop the wheels from turning with even mild slippage. This is to protect the planetary gear system from spinning/high revs damage.

It can be quite a pain and is as much a problem with the poor traction OEM Integrity tires as it is with the TRAC itself. I notice less dramatic TRAC activity on a steep gravel hill I frequently climb since switching to Michelin HydroEdge tires.

 

[KTPhil]

Question for the group:

Would the "diagnostic mode" TC override solve this? We certainly wouldn't be overrevving on a slippery surface, and it would disable TC and let us proceed.

 

[Victor]

I also managed to get very stuck on a dirt road on Crete. We spent about 5 hours trying to get out and eventually had to call the rescue services as it was getting dark. We were several thousand feet up in the mountains, over 20 miles from the next town or village. Our mobile phones wouldnt work and we had to walk about 3 miles befor we ot a signal. It took the rescue another 3 hours to find us and they decided to leave the car until the next day as it was now midnight.

So yes, the TC can be a pain but I think switching it off may not have been the answer. In our case the tires could not get grip, but they did spin a lot (flooring the gas can cause the wheels to rotate dispite TC) and we even had smoke from the tyres where they were tying to get drip on a rock.

 

[Isabelle]

Hey Victor;

Were these the original tires (tyres)? Integrities? Got to be
careful here...as Evan points out, it might not be the TC (which I like),
but the tires.

Or some other?

 

[Victor]

Yes original tyres, but in the EU they are different from the USA.

 

[C.Rickey Hirose]

Yes original tyres, but in the EU they are different from the USA.

Hello Victor. Can you tell us what brand of tire do you have or came equipped in your Prius ?

 

[marlowe7]

slippage

This is the first I've heard anyone else mention this situation. One week into my 2005 Prius, I was driving on a gravel drive high in the mountains. On a sharp turn, the road took a steep incline of a few feet. Having no forward momentum, I simply couldn't make it up the small hill. The feeling I had was that the tires WERE spinning in the gravel, but now I'm not so sure. In any event, I had to back up and get a running start.

It was no big deal, but I certainly came away with the sense that the Prius (much as I love it!) is not going to fool anyone into thinking it's an off-road vehicle. My plan is to try to avoid those kinds of conditions rather than attempt to turn the car into something it isn't.

 

[Victor]

Hey Victor;

Were these the original tires (tyres)? Integrities? Got to be
careful here...as Evan points out, it might not be the TC (which I like),
but the tires.

Or some other?

Ok Took a look at the tyre, and totally forgot to make a note of the tyre type, but its a Michelin, not a Continental. Will TRY to take a look tomorrow and note full details.