Aircon Fan Goes Off When Reaching Desired Temp

[qha_vn]

i set 74 degree F ("auto" mode), when cabin temp reaches that temp, the fan (blower) goes off (compressor goes off as well) but i think the blower should NOT go off

is this normal in LS400? and is there a way to set the fan always on regardless compressor status

[dfkd]

The computer regulates the fan speed as well as the compressor.

I've noticed that the computer regulated fan speeds have about 6 different speeds rather than the 3 we have manually.

If you manually select a fan speed rather that usingn auto it will stay at the speed you select.

[qha_vn]

thanks dfkd for your reply, i also notice the "additional" fan speed in auto mode, but aircon ECU actually stops the fan when cabin reaches preset temp (in both auto and manual mode) which i dont want. i am just wondering if Lexus designs it that way or something is wrong with my car

[wwest]

thanks dfkd for your reply, i also notice the "additional" fan speed in auto mode, but aircon ECU actually stops the fan when cabin reaches preset temp (in both auto and manual mode) which i dont want. i am just wondering if Lexus designs it that way or something is wrong with my car

In these early models the fan controller consisted of two sections, an actual mechanical relay (the idea was to totally bypass the voltage drop, however small (~1.0 volts) by the solid state controller power transisor) for high, MAX, speed and a solid state controller for all the lower speeds. Obviously your low speed solid state controller is failed.

And the LS series uses an airflow reheat/remix method to modulate, moderate, the system airflow temperature so the A/C compressor will cycle on and off all the time when "enabled" in order to provide a continous supply of liquid refrigerant.

[qha_vn]

i started the aircon today in diagnostic mode and received error code 34 (error description: Open in air inlet damper position sensor circuit. Or, open or short in air inlet sensor servomotor circuit. Or, air inlet servomotor locked) instructuctions from www.lexls.com

does the error relate to fan stop? what should i do to fix this?

thanks

[wwest]

i started the aircon today in diagnostic mode and received error code 34 (error description: Open in air inlet damper position sensor circuit. Or, open or short in air inlet sensor servomotor circuit. Or, air inlet servomotor locked) instructuctions from www.lexls.com

does the error relate to fan stop? what should i do to fix this?

thanks

1990....multiple failure points...??