see this causes and fix it. God bless youCompressor Checks
Start with the compressor. Does it engage when you turn on the A/C?
If so, the compressor is working and the A/C system probably contains
enough refrigerant to make cold air, so the problem is inside the HVAC
unit. Replace the motor that controls the blend air door (this is a
difficult job and best left to a professional since it involves tearing
apart the HVAC unit -- about an 8 to 10 hour job!).
If the compressor does not engage when you turn on the A/C, see if it
will run by jumping the compressor clutch wire directly to the battery
(use a fused jumper wire). If the compressor works when you jump it,
and the A/C blows cold air, the system contains refrigerant and the
fault is likely a bad A/C compressor clutch relay or a bad clutch
cycling switch or pressure switch.
If the compressor does not engage when you jump it, the problem is a bad compressor clutch.
If the clutch engages but the compressor does not turn (the belt will
start to slip and squeal), the compressor is locked up and you need a
If the compressor clutch engages and turns the compressor, but the
A/C still does not blow cold air, the system is probably low on
refrigerant and needs to be recharged.
A/C pressure gauge to the HIGH SIDE service port (located in the high
pressure hose that runs between the compressor and the condenser in the
front of the engine compartment). The gauge will tell you if there is
any pressure in the system. Simply depressing the service fitting valve
with a small screwdriver to see if any refrigerant squirts out is NOT
an accurate check because it tell you how much pressure is in the
system. It may still have some pressure but not enough to trip the low
pressure safety switch so the compressor will engage.
If your A/C system is low or out of refrigerant, check for leaks,
then have the A/C system vacuum purged to remove air. After the air is
out, it can be recharged with the specified amount of refrigerant. It
is important to get any air out as this will reduce cooling efficiency
and may make the compressor noisy.
A/C System Functional Checks
refrigeration circuit seems to be working (refrigerant in the system,
compressor running and building pressure), but there is still no
cooling, the problem might be an obstruction in the orifice tube
(located in the high pressure hose between the condenser in the front of
the radiator, and the evaporator located in the passenger compartment).
A blockage here will prevent the refrigerant from entering the
evaporator or recirculating through the refrigeration circuit.
If the orifice tube is plugged, the high side pressure reading will
be lower than normal, and the low side reading will also be lower than
normal because no refrigerant is circulating through the system.
refrigeration circuit seems to be functioning normally (compressor
running, frost or condensation on the high pressure line from the
condenser to the evaporator), but no cool air is blowing out of the
ducts inside the car (and the blower is working), the fault is likely a
BLEND AIR door that is stuck in the HEAT position, or possibly a badly
clogged cabin air filter that is restricting airflow. Another
possibility would be a fault in the automatic climate control system
such as a ad interior temperature sensor or control module.