DTC C1234

I had a friend contact me asking about a problem he had with his Prius after changing his battery.
The VSC light came on and would not go out.
Checking the fault with Techstream came up with the DTC code C1234 "yaw rate sensor". Clearing the code did not clear the problem the code coming strait back.
Although he has the Mini VCI he was not confidant about doing a zero point calibration, fearing he would mess something up.
I told him to try disconnecting the 12 volt battery "something he assured me he had already done", but I told him to try again, but making sure the steering was strait ahead when doing this. I also said I was not confident this would cure the problem as the manual states "change the sensor".
He went ahead and did as requested, and this corrected the problem. I think from this it is possibly important to make sure the steering is in the ahead position when disconnecting the 12 volt battery to avoid similar problems.
Obviously taking the car to the dealer would mean an automatic replacement of the sensor and a zero point calibration costing $---- .

John (BRitprius)