It is probably out of Freon or R-22. Most automotive stores can check it for you. There are gauges you can buy also to check it yourself. If that is not it, there is a switch that can also go out. It is an very cheap fix if you do it yourself.
Another cause might be the temperature blend door being stuck in the hot air position.
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mercury sable
The 2000 Mercury Sable starter can be found on the right hand side of the engine. The starter will be near the back of the engine.
on the steer wheel
The 2000 Mercury Sable starter will have three retaining bolts. There will be two cable retaining nuts on the front of the starter.
On a 2000 Mercury sable : firewall 1-----2-----3 4-----5-----6 front of vehicle > driver
torque specs 2000 mercury sable 3.0 12V rod bolts
In a 2000 Mercury Sable : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
There is a thermostat on all cars.
no it will not
firewall 1-----2-----3 4-----5-----6 front of Mercury Sable > driver
According to the 2000 Mercury Sable Owner Guide : Motorcraft MERCON automatic transmission fluid is used as the power steering fluid
According to the 2000 Mercury Sable Owner Guide : ( Motorcraft MERCON - V , automatic transmission fluid in both types of automatic transaxle / transmission )