There is no fluid, the steering is driven by a motor which engages directly with the steering column, this applies to the 1.6 & 1.8 vvti the diesels 2.0 & 2.4 vvt all had traditional Hydraulic PAS.
And just for general info:
All MK1 where Hydraulic PAS
All Mk3 are electric shaft type PAS
Hi
Think I bought some for the wife's yaris from here: https://www.ebay.co.uk/itm/4-x-Genuine-M12x1-5-Flat-21mm-Alloy-Wheel-Nuts-Toyota-Yaris-99/181699956113?epid=1788738621&hash=item2a4e294d91:g:Kg0AAOSwMYRaX6lR
Seem to have survived the winter ok. still seem shiny and have been loosened a few times with an impact gun and a 21mm chrome moly socket.
Hi Janet.
Have a read of the link below, it may help you.
https://www.telegraph.co.uk/motoring/caradvice/honestjohn/7620984/Toyota-Yaris-gearbox-problems-Honest-John.html
Mike.