Traction control engages at high speed

Double check that the tire pressures are all close to where they should be. Most here recommend near 40 psi for best mpg, slightly more in front than rear.

 

Faulty wheel speed sensor(s)?

SCH-I535

 

The sensors are located behind the hubs on all 4 wheels. you need a scanner to read them, but before you worry about that, check your tire pressures and make sure the tire shop didn't accidently put a different size tire on your car. wouldn't be the first time a tire jockey pulled 1 or 2 wrong size tires and slapped em on the wheels without looking. generally if the wss is bad it will throw a code.

 

Since you noticed this you HAVE checked the tire pressures......right ??

Your profile doesn't indicate where you are but I think it is possible that cold weather, new tires and a jerk installer putting in WAY too much air might be the cause.

If you don't find anything else, try running them at the Toyota recommended pressure for a few days or weeks until they get "broken in".

 

----both tires same size---- so did you replace just one set or all 4 ? Just trying to find some size difference that could be causing this..

 

Try deflating the fronts a bit to compensate for their larger diameter.

 

Just because tires are the same "size" doesn't mean that the rotate the same "revolutions per mile". Are the new tires the same brand/model as the old tires? If not, what brand/model tires are the old ones and the new ones?

JeffD

 

You would need the mini VCI to monitor the wheel speed sensors. If there was a hard fault with one of the sensors, there would be a DTC set immediately, and the ABS and VSC lights would stay on. If one of the sensors was bumped during the tire change operation, it might have the consequences you are seeing, but I would more expect the hard type of fault in that case. To inspect them you would have to take the wheels off and have a look. Not too hard to see them.

 

any decent scanner can read the sensors; you hook it up to the obd port and drive with a friend to monitor the wheel speeds. know any technicians?

 

Possibly a slipping torque-limiter.

 

Set the front tyre pressures to 40 psi - no more than that. Set the rear tyre pressures to 38 psi. Go for an extended drive that involves cruising at the speeds you previously mentioned. Make sure the road your're doing this on is NOT a rough road. If you're still having problems, then either one of those tyres has a manufacturing fault, it's the sensors that are indeed faulty (never heard of this before....), or maybe your brakes are faulty and "grabbing".....without your knowledge and need overhauling.......also extremely rare.

Hope that helps.
Let us know the outcome please

 

Do Prii have torque limiters?

 

Yes, there is a torque limiter between the ICE and the HSD. It rarely causes problems.

JeffD

 

A slipping torque limiter will also throw a DTC, but this is not the cause of the OP's problem. Also the best "new" tyres should be on the rear not the front of the car. If all the tyres are the same size apart from ware difference a scanner such as the VCI is the only way to diagnose the problem.

John (Britprius)