Yaris steering not self centering

[anchorman]

21 minutes ago, monkeydave said:

think they all do it with the electric steering my 2004 does it with less than 7000 miles on it

 

dont know about the pre face lift ones with hydraulic steering

 

you just get used to it

It shouldn’t.  

[Ted Striker]

A 'paper clip' test has revealed 2 fault codes with the power steering ecu being common to both. Does anyone know where this ecu is located and what's involved in accessing it?

[anchorman]

Have you cleared those codes and run them again to see if they’re still there?   You’re thinking too hard, it’s a uj on the steering column.  

[Ted Striker]

They return 

[anchorman]

1 hour ago, Ted Striker said:

They return 

That’s where understanding these OBD codes can be confusing because they can and often do show the effect and not the cause.  Makes no odds to me if you chase your tail.  

[Ted Striker]

Before contemplating taking out the dash I decided to double check that it wasn't a mechanical issue so got the car in the air. Firstly the track rods were disconnected, struts turned freely so not ball joints or top mount bearings, then disconnected the steering column at the knuckle joint, absolutely no difference to the steering, still sticky and reluctant to move which means it can only be be the EPS control module or the EPS motor. Not sure I've got the inclination to take the dash out so I may just sell the car off cheap. 

[anchorman]

7 hours ago, Ted Striker said:

Before contemplating taking out the dash I decided to double check that it wasn't a mechanical issue so got the car in the air. Firstly the track rods were disconnected, struts turned freely so not ball joints or top mount bearings, then disconnected the steering column at the knuckle joint, absolutely no difference to the steering, still sticky and reluctant to move which means it can only be be the EPS control module or the EPS motor. Not sure I've got the inclination to take the dash out so I may just sell the car off cheap. 

You disconnected the steering at the knuckle joint and did what?  Just turned the wheel?  There’s more than one knuckle.

[Ted Striker]

Update on the power steering saga. After stripping down the dash I removed the power steering ecu but then couldn't find anyone to check it for faults or recondition it . After finding that new ones are now discontinued I took a chance and got a  cheap used one and put it in. Rather than refit the entire dash I plugged in the instrument pack and tried it. No difference at all but I did notice that initially the steering didn't seem too bad but after you'd travelled a few miles it got worse, presumably as the electrical components warmed up. Next I unplugged the ecu and also removed the power steering motor which I unplugged but left behind the dash and tried it again with no power steering whatsoever. Obviously the steering was ridiculously heavy at low speed but at higher speed it was apparent the stickiness in the straight ahead position had gone. I  then took out the motor properly and on initially spinning the output shaft found it sticking and notchy but after spinning it around a few times it freed off. I refitted it, reconnected the electrics and tried it again. Steering is now OK. Will run the car for a little while before refitting the dash properly but the issue did seem to be attributed to the EPS motor. Don't know why the motor had partially seized up but for the moment seems to be working as it should.