Auto Air Conditioning & Heater Repair: air condition problem 95 dodge ram 1500, dodge ram 1500, air condenser

Question
QUESTION: 95 dodge ram 1500.My air line to front rad is frosting up and my air condenser is turning off and on when heat or cool knob is turned on.It runs fine if i have the knob in the off position.

ANSWER: HI Doug

It sound like your control is not turning off the compressor.  Check and see if your compressor is off when you turn the system to heat.  Pull the actual knob off the control and check for cracks in it.  It may not be moving when you think.

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QUESTION: it doesn't matter if the system is turned to heat or air.The only way the compressor stops going on and off every 10 seconds is if i turn the control knob to the off position.I pulled the dash off and checked for cracks and also to make sure vaccum lines are attached everything looks good.Is their any module or switch that can be the problem that causes the compressor to keep going on and off even if heat knob on dash is turned all the way to heat.

Answer
Not sure if the knob you are saying is the one with the line red to blue.  If it is then make sure you turn the main control knob to heat.  If you leave it in max or defrost your compressor will turn on.  Also check for anyone that has messed with your electrical.  If everything is OK then your control head is probably bad.