T Sport Power Steering

[Kozzy]

When parking the car this morning I noticed the steering bacame really heavy and the 'PS' warning light came on.  I didn't have time to look any further as I had just got to work. 

When I get back to the car later what are the logical steps to diagnose the issue?  I am assuming this is an electric motor system rather than hydraulic and so no fluid to check?  Can I get any error codes out without using a reader? (my Subaru Impreza had a flashing light counter system for reading error codes, for example).  What are the likely culprits, baring in mind this happened as I was turning the wheels quickly one way to full lock and then the other?

Car is a 2004 Corolla T-Sport

Cheers,

[fordulike]

The electric power steering relies heavily on receiving a good flow of current from the Battery and alternator. Might be worth checking both of these are in good working condition.

[Kozzy]

Will a falty Battery not generated other symptoms at the same time or is the power steering particularly susceptable? Is there an easy way to get the actual error code generated?

[DeTomato]

Worth also checking fuse / relay connection. Build up of resistance on these can make it appear it's not working when all that's happened is the current isn't enough to make it work.