Hello , i have a Gen 1 Prius and it has a problem with steering wheel. DTC errors are C1571 , C1572 and PS red light is On . When i am turning the wheel , at random times the wheel starts vibrating hard. It makes noises from the vibration. This lasts for 2-3 secs then it stops vibrating. After this at random time when turning it , it will ocur again . This can happen 2-3 times per minuite.
I'm writing on my phone but that's a well-known first gen Prius issue. There was a warranty extension but I think you're past the end date now. The underlying cause is no different from the other gen1 issues related to old potentiometers getting noisy (big hand syndrome, heater servo tremors), except the steering torque sensor is a lot more work to get to and clean. I finally bought a cheap one from a junkyard just to figure out how it comes apart. Look for a thread called "steering gear jitters". -Chap
I had the vibrating steering wheel when turning just after I purchased my 2002 Prius just last year. I found the little 12 volt battery located in the driver's side of the trunk was caput. As I understand this little battery is not used to start the generation 1 Prius. The vibrating steering wheel has not returned.
