Steering Angle Sensor

I have a 2015 Prius trim 2, 127K. I bought this car with the anti skid light on constant. First scan said no faults. So, I found on YouTube a calibration method of jumping pins 4 & 13 on the OBDII. Anti skid did not go off. Second scan, I now have c1231. So, I connected my Maxicom MK808 and went to live data. There I could see the steering angle sensor stuck at 850.5 degrees. No response in turning the wheel. My question is if it doesnt move is it the clock spring thats bad or is it the angle sensor not responding that is bad? I'll probably buy both together assembled if no one knows the answer. But if it is one of the two parts, the clock spring or the sensor is there a correct meithod of assembling the two? Its says on the sensor do not remove from clock spring. I imagine the spring becomes unwound and then needs to be correctly wound back up. Can't seem to find that info, although I see on youtube people spinning the sensor back and forth and then aligning at 12 oclock. No explaination of what exactly they are doing. Hoping someone here has run the gammit and knows.

 

Thanks, I agree it's more likely the sensor only. But in searching aftermarket sensors only on Ebay, part #89245-74010 for my 2015 Prius seems to span only 2010-14. I can find that same number for 2015 but its complete with the clock spring and with the same sensor #89245-74010 attached to it. Strange. As funny as you mentioned that Toyota doesn't trust us DIY'er it seems for 2015 you have to buy the whole assembly but if you have a 2014 you can buy them separately (?) So, I could buy the sensor only and attached it to the clock spring against Toyota apparent restrictions on how they sell these things. It's just kinda strange. Dealership gave me part number 84307-47020 for the whole assembly. Only $649! Compared to $50 sensor only on Ebay.

 

Yeah, I decided to buy one from someone parting out a Prius. Its OEM and not China aftermarket. Clock spring and sensor together, not guessing, hopefully only have to do it once.

 

So I bought a used OEM steering angle sensor and it did not solve the problem. In diagnostics on my Maxicom Mk808 testing ABS/ECB sensors it found the C1231 again (still stuck at 850.5) but also noted that all wheel sensors had low or abnormal readings. But, code c1281 said the master cylinder had a low sensor output. Not sure exactly what this means. None of these codes show up in a scan. I found them by testing. There is the master cylinder atttached to a black electronic box, the anti skid control unit witha a pin connector connected to it. Manual says to check wires, pin and secure. I'll check that. Called toyota they said that the master brake booster is on voluntary recall. Meaning the dealership policy decides if they will replace this. Must be under 150k/ 10yrs. However, my car is a salvage titile and that may void the voluntary recall.
Has anyone gone down this path before? Am I on the right track looking at the master brake and anti skid control unit?
PS: dome lights work fine

 

Thanks, the online manual behind the paywall? Not sure what that is. any online manual?

 

I continued my diagnosis and in doing so managed to get more trouble codes. I believe its because I cleared memory for G and Yaw sensors. This produces the abs and brake light. I have been able to get out of this by doing a linear valve offset and those codes disappear once the procedure is complete. But, this time after doing the required memory reset for the abs the linear valve offset wont work and i have four codes insead of one. I'm thinking my skid control ecu is messed up and not responding. It has low abnormal output to all abs wheel sensors and the traction light is constant and the steering angle sensor is stuck at 850.5 I have a shop manual on the way so I can check voltages but i suspect its the skid control ecu.