Vehicle Stability Control,

I've encountered the same problem going up a not too steep gravel driveway. I wound up having to back up the driveway to get to the top.

Unfortunately, I'm pretty sure the VSC can not be turned off.

 

Brian of BT Tech in his dyno tests thread found a way to permanently disable TRAC. Unfortunately, it also disables ABS, VSC, and probably EBD (electronic brakeforce distribution).

[edit]
As what PriusEnvy says, Traction Control is what you're encountering.

 

For the thousandth time:

That's not VSC, that's TRAC!!!

 

If it were VSC you would hear the beeper, I don't remember hearing it for traction control. Anyway priusenvy is correct it is traction control in the circumstance you describe, and neither trac or VSC can be turned off in the Prius. Some cars yes, but not this one.

 

Only solution is to get better tires. Tons of threads here covering choices and experiences of drivers with alternate treads.

Your not the first, this comes up with the weather change, especially snow.

 

IMO, Toyota really should have provided a switch to turn off the traction control for the reasons mentioned in this thread.

The ONLY way I was able to disable the traction control (VSC) was to physically disconnect the rear sensors on the hubs. This way the computer has no idea what the rear wheels are doing in relation to the front wheels and sets an error code which disables the traction/abs control.

The EBD (electronic brakeforce dist) is not affected.


Thanks!!

Brian
BT Tech
305-652-3115

 

Does anyone know for sure if the traction control on the Prius is there to protect the motors? I think the computer could, and most likely does, do that by limiting the frequency of the power from the inverter being directed to the motors. Maybe they were just a little over conservative when they designed the traction control? It would be very useable if it didn't try to limit the front wheel speed based on rear wheel speed, or maybe allow the front wheels to go at least a little faster than the back ones. It would seem that all it should do is to keep one front wheel from turning a lot faster than the other. I am not trying to out guess the design staff but I sure am curious why they did what they did.

 

I owned a '99 Prius for about three years and drove it everyday on the snow-covered roads of Hokkaido. I always felt very safe in that car. I can recall a few times when, in driveways after a big snow, my car would be almost stuck. After the tires would spin a little, it seemed like the power would just cut out. A little gas- nothing. Full gas- nothing. When this would happen, I would put the car into reverse and sort of rock the car out of position by repeatedly pushing down and letting up on the gas, but not all the way. This always seemed to work. It actually worked for going forward too, but it had to be done a little bit in reverse first.

Now, I'm interested to see how my '05 will perform this winter.

 

You can disable VSC, basically that amounts to jumping 2 pins on the DLC. However as stated, VSC is NOT trac. Trac is your problem. Yes, it is documented in Toyota's technical site that trac is used to prevent damage to the PSD.

Now as for saying the car is dead, that is hogwash. The tire has to turn in order to detect lack of traction. Most of us can be overly agressive with the accelerator, especially when we are not aware that we are on a slippery surface. Once the car stops the wheels, it will retry turning the wheels again. If you have the accelerator at the same spot, you will get the same results: stopped wheels. If you instead gently accelerate, you might be able to move, if movement is at all possible.
When you know you are walking on a slippery surface, do you run through it, or take careful steps, almost tiptoeing? So why do we expect to run our cars through slippery surfaces and get suprised when our cars finally tell us NO!

You can put the car in maintenance mode, which turns off TRAC, but also has the car ICE run at set RPM steps based on accelerator position.

 

The classic did have a rudimentary form a TRAC. It wasn't really for driving it was just to protect the electric motors. There was some sequence that you could enter on the MFD that overrode it so it could run on a dyno.

Funny on the classic I hardly ever spun a tire. Now with the '05, which isn't that much more powerful, and the onset of the rainy season I keep triggering the TRAC.

It's amazing, the POS OEM Goodyears may be worse tires than the POS OEM Bridgestones on the classic :angry:. The Cubs will win the pennant before I go out and buy either of those disreputable brands.