Reader Question I have a 1999 Pontiac Grand Prix Daytona Pace car. I have a problem with the dual climate control. When I start the car for the first time in the morning the digital readout shows the outside temperature reading almost in the freezing area when the actual temperature is in the 90’s.
Therefore, my air conditioning will not blow out any cold air until the read out climbs above 60 degrees. The only way it will climb away from the freezing read out is for me to get on the highway and drive at a steady speed (around 65mph) for about 3-5 miles, the readout starts to climb to a temperature that is closer to the real outside temperature. However, if I stay in town and do not get to a steady high speed, (like stop and go traffic) it never changes. It seems like the thermometer is not working any longer.
I bought a repair manual and looked for anything that would lead me to where the problem could be, but all it shows is replacement and the steps I would need to take to replace the complete unit. I want to make sure if I replace this dash control head, that will solve my problem.
On the other hand, is there a thermometer somewhere that may need replaced or just cleaned? Where dose the temperature read out get its data.
Thanks in Advance
Hey there Larry,
My top auto AC guy says this:
I would replace the “ambient outside temperature sensor” first and see what happens. It is located behind the front panel mounted to the radiator air baffle. Has two wires to it, yellow and light green with black tracer. This is a dealer only part…I think, but A/C Delco might also make it available at the auto parts houses.
I hope he is correct, let me know what happens will ya?
Reader Follow up
You can tell your top AC guy he was right on with that fix. I replaced the Ambient-Outside-Temperature-Sensor located in front of my radiator, on the left hand side, attached to the plastic panel, about midway down.
I noticed the connection pins were a little rusted when I removed the old sensor. Therefore, I clean the pins then applied and little electrical connection lubricant before I connected the plug into the new sensor.
I started the car and the readout on the Climate-Control Head unit displayed the correct outside temperature. The AC system started immediately. This morning everything still is operating as planned.
Note: The part only cost a little over 10 bucks.
Thanks again for your time and the correct analysis.