On our 2004 S Type while in auto mode and the temps set at 70 degrees the system goes from blowing nice cold air to heat ll by itself and the only way I can keep it blowing cold is if I set the temp all the way to low. My question also is how many interior temp sensors are there??

 

There's four one on the passenger side and two on the drivers side going into the ac/heater unit and one behind the little grille above the ignition switch.

 

Okay I have cleaned those and still have the problem with it changing from cold to heat at anytime what could be the problem. Help ???

 

You need to search some here. You have a very common problem and you will soon find out the most likely cause.
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