I was running the car with the heat blowing and I plugged in my 12v Garmin GPS into the cigarette lighter. The heat stopped. When I try to turn on the controls nothing shows up on the LCD, no air is coming out of the vents, none of the AC, defrost buttons are working. The green background of the LCD is on but it does not show any mode controls.

All other electrical systems seem to work fine. I checked the AC/ defrost fuse in the driver panel fuse box, it is ok. I bought a new heater relay, that didn't work.

Is there a simple fix like buying a blower realy (if it exists). The Lexus manual does not have any information about the relays, just the fuses.