Ac has stopped working no pressure drop accross the compressor is there something besides the compressor that could cause this?

Incorrect coolant pressure is most likely the cause.

This is usually caused be low Freon in the system. There is a low limit switch and when the pressure drops the switch opens the compressor stops.

There is no need to add oil to an ac compressor unless you have had a massive leak. new compressors come with the right amount of oil. The compressor oil circulates with the gas and by the time the gas pressure drops from a leak then the amount of oil leaked out is just a few drops. Excessive oil in the system stops the TX valve from working and causes problems . If still in doubt then talk to an accredited ac specialist

Depending on how much freon is in the system, it could be a faulty low pressure switch or a faulty clutch.
You would jumper the low pressure switch to eliminate it for a test.

look for air bubbles in the dryer peep glass
if system is out of gas air con compressor clutch wont kick in
clutch is replaceable

at a rough guess you add excessive amounts of freon and that caused the compressor to seize up
gas is added using pressure gauges and not by the can
besides that did you use the correct gas as the r134a runs at a much higher pressure and will deliver liquid back to the compressor which is not good for the operation

You charge it at the smaller of the two AC lines from the compressor using a pressure gage, when the low side pressure is at 28-32 PSI the system is charged, I think you are overcharging the system which loads up the engine and causes it to slow down. CHECK THE LOW SIDE PRESSURE!

Jumping the switch is only recommended for very short periods of time to check the compressor itself. The problem with straight-wiring it is that the compressor will run all of the time. During normal operation, the compressor cycles on and off depending on the pressure inside the A/C system. If you run the compressor all of the time, you run a risk of causing substantial damage to your A/C system, your car, or even yourself. The compressor would be constantly pressurizing the system until something releases that pressure. It may be an A/C hose or it may cause something larger to explode under the tremendous pressure. Be very careful with the A/C system and get the advice of a licensed A/C technician.

Go to wal mart $6.00 a 12 oz can,may need 2 cans. Car owners manual will tell capacity in oz of AC system never charge over that amount into your system, also PSI and ounces are not the same thing

Go to auto parts store buy R-134a charging hose kit with a gage built in.$ 10.00

Turn engine OFF Under the engine hood, is a large aluminum cannister usually on passengers side ,on it or on a hose coming out of it will be a black plastic cap,with a connect fitting under, remove cap, pull and hold back the locking ring on the charging connector and push on fitting. look at gage it will show how much freon pressure is in system, with engine and ac off a higher pressure value will be on gage Start engine and turn ac on cooldest and fan high. The pressure will drop. if the pressure drops below about 22 PSI the ac compressor will stop automatic by the low pressure cut out switch.then the pressure will build above 25 and the compressor will engage again, this is short cycling(no/off) on the low pressure sensor and is a good indicator of a low charge of refigerant(R-134a). Charge according to instructions on kit. When the pressure stays above 28 and the compressor stops cycling off your good DO NOT over charge or you can cause compressor slugging. Liquid into compressor($1200.00 for new compressor)
SAFETY!!!!
R-134a can cause blindness. wear goggles and gloves

The "O" ring seals in the ac system dry out when the ac is not in use for over a month and leak the refigerant out again, So Use your defrost setting in the winter because it runs the ac compressor for dehumidifying, but only after the engine has warmed up a little, or with no warmth from engine the defrost will blow freezing air.

Patrick Mot

check the psi level on the system, cause you may have a leak and the system dropped the pressure level, if the level is fine then replace the compressor, cause it it probably bad... hope this helps you...