that 's tell you that the brushes in the air blower are gone and you need to buy a new blower usaly cost around 150 dollars
It could also be the blower motor switch or resistor, I had an intermittently bad switch that would cause "medium-high" to go regular speed and very slow. If the blower fan works good in different positions like high, then it could be one of these other 2, usually cheaper and easier to replace items.
Toyota previa starter motor wont engage
All the fuses are located in the center dashboard. To remove it, find the clip under the center of the lip and press it up.
how to install a blower motor for a 1994 Toyota pickup
2004 toyota blower motor location solara
how to install a blower motor for a 1994 Toyota pickup
Raise the hood, remove the inlet shroud to the blower housing, then remove the top half of the radiator fan shroud. Next start removing the screws that hold a protective cover that is below the blower motor. There are 4 screws and one bolt that secure this. Let this cover drop down and then the blower resistor can be seen behind the blower motor. Remove the electrical connection plug and then the two screws that hold the resistor in place. Go to this site for great Previa info: http://autos.groups.yahoo.com/group/previa/
open the hood remove the air intake funnel remove the base of the air duck and you will find the blower..
SAE 10w30
the resistor for the blower motor is busted blower works on high with out it
Check the resistance on the blower motor.
How do you replace a defrost blower motor in a 2003 Toyota Corolla
Common causes, blower motor resistor, blower motor, wiring or controls