PontiacBonnevilleClub.com

My '93 Park Avenue Ultra has an issue with where the heat goes, the drivers side gets the heat as does the back seat, but for the most part the passenger side gets cold air. Same with the defroster. So the heater core works, but where the heat goes does not. We removed the glovebox and I can sometimes see the controller for the passenger side open & close so I'm thinking whatever sends the message to that side isn't always sending it like it should.it opens then closes at startup of the car. I did get a trouble code out of the heater, it reads 41, but the codes I found are; 40 or 140 - Driver Air Mix Motor circuit open or shorted, or not calibrated.


Maybe 40 is the driver side, and 41 the passenger side?

if you have seperate controls for passenger and center controler try setting them both too same setting then disconnect the battery for 15 minutes ( you will loose codes) then reconnect and see if they "relearn" and calirate