saleenssc

1998 LS400
with NAV/Radio/Hvac option
180k miles

Temps in Virginia have been in the 30's lately

on my way home from work last night i stopped to get gas. after filling up and starting the car i noticed my hvac fan was not working. i checked my display and all the push buttons on the screen were responsive, but it just would not blow any air. about 2-3 mins later it started working again. i made sure to select the floor vents, floor/face vents, face/windshield vents...all setting work like they are supposed to. also this morning hvac seems to be working ok. Any ideas what could have caused this. could the cold temps outside have something to do with this. Is my display showing signs of failure?

thanks

Kansas

Did the radio work at regular volume when this happened?

Has this car ever had the Lexus dealer installed car phone? Two of the features of the Lexus car phone was to reduce the HVAC fan speed and mute the radio. The phone transceiver was located under the floor on the right side of the trunk. Sometimes pins in the connectors to the transceiver would short out causing radio mute and no/low fan speed even after the transceiver was removed and discarded - particularly if the connectors were left dangling and touching the floor. I know from experience that there is a particular pin in one of trunk connectors that muted the radio - its location is shown in a thread I posted on this forum many years ago. IIRC, that particular pin did not also reduce the fan speed so they might be a different pin in the connect that did that.

If the car never had a dealer installed phone then the connectors I'm talking about will be attached to a plastic bracket on the bottom of the tool kit receptacle and I doubt they could get wet and short out in that location.

saleenssc

i cant recall if the radio was on at the time. Yes my car does have the factory installed phone in the armrest. It hasnt powered on in 15 years. No issues with the HVAC all weekend.

saleenssc

The problem occured again yesterday as i was leaving work. Temps were near 70 this time. I went to turn on my a/c and i noticed the car was too quiet inside. upon closer inspection i realized that my fans were not blowing air. All of my touchscreen buttons were working on my nav/hvac display, my radio was working, including volume and preset station buttons. However after about 10 mins of driving i noticed the fans starting blowing air inside the car. No issues the rest of the way home. Got in my car this morning and everything was working as it should. my car does have the factory installed phone.I have not checked my trunk yet to inspect the transciever.