Air control blowing cold air

[stock93cv]

My 03 MM seems to warm up just fine (with its auto setting temperature control during which it blows warm air--I have the auto set to 20 degrees), but after maybe 10 minutes it starts to blow cold air. Has anyone else experienced this? Even though the cabin is well under 20 degrees, the fan still blows cold air and continues to blow cold air until I get to where I am going. Then, when the engine has cooled off and I head for home, the whole cycle starts again--maybe 10 minutes warn, followed by COLD air for as long as I drive until the car is turned off.
Any ideas?
Thanks.
Stock93.
Oh--I am talking about Celsius degrees, so 20 equates to 68 Fahrenheit.

[Murader03]

Don't know how many miles you have on the car, but I'll tell you what happened to mine.

For a couple weeks the car would heat up, buy the temp gauge, but would not get warm inside. Then it would start heating the interior. The thermostat was sticking, and finally stuck closed altogether and caused overheat of the engine. May not be your case.

In the auto mode, when mine is set to 70, it heats up fine and then starts blowing the cold. I believe it's cycling between heat and a/c depending on how the temp sensor preceives the cabin temp to be. Is it a problem, I don't know..bears watching, errrr feeling

[BillyGman]

I'm not sure if you're talking about the heat, or the A/C. if it's the heat you're speaking of, then the following applies: Usually if the thermostat is stuck closed, you can feel that there's a big differnce in how hot the upper and lower radiator hoses feel to the touch after the car has been running for atleast 15 or 20 minutes.

I think the same symptom would occur if the waterpump wasn't working properly, however, if that was the case, then it's likely that the temperature gauge would climb up into the overly hot range, and eventually the engine would over heat. Another possible cause of what you've descibed can be that the coolant level is too low due to a slow leak somewhere in the system. So I'd suggest you first start w/the simple stuff like checking the coolant level in the resovior tank, if you haven't done so already.

[jstevens]

Check some earlier posts but I think someone said you could test the auto climate control by pushing the defrost and vent button at the same time.
I could be wrong about which ones you push and hold but that might help to diagnose your problem.

[ParkRanger]

Currently having a similar situation. A/C will blow hard, especially when engine just started - to the point that engine heat climbs to "high." Will turn climate system "off" and engine temp returns to normal. Will then turn A/C back on again but will continue to blow cold, even when temp set at 80. Will get it checked next servicing. Keep us updated on yours. :confused:

PR

[Smokie]

My 03 MM seems to warm up just fine (with its auto setting temperature control during which it blows warm air--I have the auto set to 20 degrees), but after maybe 10 minutes it starts to blow cold air. Has anyone else experienced this? Even though the cabin is well under 20 degrees, the fan still blows cold air and continues to blow cold air until I get to where I am going. Then, when the engine has cooled off and I head for home, the whole cycle starts again--maybe 10 minutes warn, followed by COLD air for as long as I drive until the car is turned off.
Any ideas?
Thanks.
Stock93.
Oh--I am talking about Celsius degrees, so 20 equates to 68 Fahrenheit.
Have you tried to heat the car manually with the FLOOR setting to 20* if so, what were the results ?