A problem just started on my 1999 GS300 climate controller. My blower speed is either at full blast or about half. All of the buttons work and the fan speed indicator lights will move in both directions, just not the fan speed. It's weird, one day I can hit the auto button and the fan runs at full speed, and another day it might be at half speed. One night I disconnected the battery cable to reset the computer, and that did solve the problem, climate control worked perfectly. The next morning it was acting up again.

Any idea what is causing this problem, or a solution to fix it?

 

Don't know if these cars have a blower motor resistor or module, but that could be it.

 

try the fan speed servo.

there are essentionally 4 servo's and 1 blower in the system

- driver side temp adjustment servo
- passenger side temp adjustment servo
- fresh air/recirculatory air servo
- vent adjustment servo
- fan speed servo ( i believe this is on the blower itself)

 

These is a thread about repairing and another about replacing. I repaired mine and they're good to go.

 

Can you provide a link to the thread / repair?

 

I received a new blower motor control today from Lexus of South Atlanta, installed and everything is working normal again.

Part# 87165-22050 $179.74 plus shipping.

Had to remove the glovebox, CD changer and loosen a wiring harness here and there. Not the easiest part to get to, but a little patiences will payoff.