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my heater controls all work properly, blows hot. but when i turn the heat on my air conditioning pump turn on for 2 seconds then cuts out for 3 seconds then back on for 2 seconds then off for 3 seconds, does it all the time and i hate it. Even when i put the air conditioning on full blast it does the same damn thing, on for 2 seconds off for 3 seconds on for 2 seconds off for 3 seconds. every time it engages for the 2 seconds it is on my idle drops abouts 100rpms which i think is normal because the drive accessories are working harder but i need help here. how do i fix it so it operates properly.
 

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Sounds like it needs a charge. If you run the heat in a differnt mode then defrost I believe it will not come on.
 

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low charge (you have a leak)

You can easily confirm this.
Find the LPCO switch (low pressure cut off). Short the two wires to it i.e. pretending the system is not at the lowest pressure.
Do not hold this for a long time, just a few seconds to confirm - you will see the compressor slutch stay ON.
If so, you have low pressure.

remedy is to find the leak, recharge (and maybe check oil level and add some...)
 

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I should have explained a bit more...

The system is supposed to cycle ON/OFF. It should not stay ON. The purpose of this is to best maintain a balance of low and high pressure, high side liquid refrigerant and discharging at the expansion device in gas form.
Yours is cycling quickly most likely becuase as soon as suction begins (compressor clutch engages), the system dischages just enough refrigerant into the low side to cause the high side to go below the low pressure cutoff point.
A normal system will likely run for 10-15 seconds and ten stop for 5-10 seconds, etc.. however it depends on environmental conditions such as ambient temp, airflow throguh the condensor (to cool the high side and decrease the high pressure), etc..

Hope this helps.
 
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