2001 dodge neon has high ac pressure

u sound like your describing an AC system w a blockage in it. Is the compressor going on & shutting off ? Any air at all blowing? Hot/cold/cool air?

high side could read anywhere from 180 to 240 low side will read from 28 to 50

Hello, You have two switches which work off the pressure of the Freon. Both of these switches cut off the power to the compressor. One is for HIGH pressure and the other is for LOW pressure. Check for power at the compressor clutch connector harness while the controls are set and the engine is running. You may have power and a bad clutch.

When you say that the Freon pressure is good, does that mean the pressure is within the proper range? Too much Freon will make the HIGH switch cut off power and too little will make the LOW pressure switch cut off power.

The ideal amount(ozs) of Freon is what is recommended by the Manufactuer and it will provide a moderate amount of pressure of about 35psi-40psi. You can borrow pressure gauges, called Manifold gauges to measure your system at autoparts stores with loaner programs.

The low pressure side of the system is the one you use to induce the Freon to go into an empty system. You can bypass this switch by taking off the connector and putting a "U" shaped jumper into the harness and the compressor clutch should get power to LOCK up all of the time.

You can take off the switch connector at the compressor clutch and then check for power when bypassing the HIGH pressure switch if the LOW pressure switch does not make the system get power. Only, really only bypass the HIGH pressure switch with the clutch connector disconnected. The HIGH switch is there to prevent damage to all of the components from seals to lines to every piece of Freon hardware in the car. Bypassing with the A/C clutch disconnected will allow you to know if power is getting to the compressor clutch.

Finally, you can get FREE wiring and fusebox diagrams through Autozone.com. Just sign and register to their site and then you can print the documents for yourself.

Good luck with this repair and I hope my solution helps you.

If the high side got up to 375, your electric fan probably did not come on. Fan relays are always an issue. Underneath rt headlamp assembly. Make sure fan works with a jumper as these go too, and will take out the relay

you need the compressor running to get freon into the system
using gauges on a manifold you allow the compressor to suck the gas in to the system until you get a pressure reading at the high side gauge
That is the correct amount of gas for the system
take it to an accredited ac specialist shop to have the job done properly

It seems that you have a leak, best bet is to bring it to someone with a set of gages to check the pressures while the ac system is operating. The high side should be about 150-200 psi and low side between 30-40psi with those numbers you should be running very cool. If its not that high then you most probably have a leak in the system most probably at one of the recently replaced parts or a new place, fill the system with a uv dye and recharge. drive for a week or two and check with a uv light.

either your R134a is leaked out ore you need add and also add a dye see if leaks.
Add to the low side the car while running with gage with ac cranked on high follow metter dont over fill it loc the ac up. Easy 20 minute job wallmart sells the gage and R134s and so do auto zones

the a/c system needs a minimum pressure before the system will run. the system must have a leak so just buying freon may last a day or a few months depending on the size of the leak. also leaking freon into the air is ozone depleating, it should be recovered properly.

the system needs to be recoved of all freon. vacuum to -30psi held checked for leaks. (uv dye or nitrogen and soapy water). leaks fixed. vacuum to evacuate moisture and air. refilled with proper amount of freon (too much or too little make the air not as cold).

It sounds like you over charged the system, the low side should be 40psi to 50psi with the A/C on high and the high pressure side should read 150psi to 200psi. Anything different, you need to get the system service and try not to use your A/C to prevent the compressor from any damages. Good luck and hope this helps.

could be your pressure switch.if to much freon was put into the system your pressure control switch will automaticlly shut down the system.try taking a little bit out at a time and see if the clutch on the ac is engaging.