A steering wheel that does not turn is usually an indication the power steering assembly is malfunctioning. There are several components to a power steering assembly that must be checked to determine exactly where the problem resides.
O'Reilly Auto Parts suggests starting steering problem troubleshooting by checking the power steering fluid levels. If the fluid level is low, this may point to a leak within the system or a problem with the power steering pump. If topping off a low fluid level does not fix the problem and the attached hoses show no sign of leaking, the power steering pump belt should be checked next. Loose belts should be tightened properly, while a broken or damaged belt needs to be replaced. If the belt is in good condition and properly tightened, the next step is to jack up the front of the car and check the steering assembly. Car stands should be used after jacking up the car, and the car must be turned off before proceeding. An assistant should attempt to move the steering wheel while the troubleshooter checks the assembly for damage or leakage. If nothing can be seen, the car should be taken to a repair shop.