A/c light won't come back on after shutoff and restart.

[gale]

The hi/lo refrigerant pressure switch is mounted on the receiver-dryer. On most models the dryer is mounted in the engine compartment, down low, behind the right headlights. You might have to remove the airbox and washer reservoir to get to it.

[mossyoaks]

I was trying to avoid having to have the "a/c professionals" having to get involved. Will changing the pressure switch open up my refridgerant system?

The hi/lo refrigerant pressure switch is mounted on the receiver-dryer. On most models the dryer is mounted in the engine compartment, down low, behind the right headlights. You might have to remove the airbox and washer reservoir to get to it.

[Guapo]

You're probably low on refrigerant. I had the same issue, and in testing for leaks, we put in some UV dye. As soon as I had a bit of coolant in the system, the AC light would come on.

We found the leaks at one of the schraeder valves and the seal to the compressor. I am currently awaiting a new compressor.

Have your system checked for leaks.

[Tiger]

Forget about the switch. Yes, it will blow out with all youre refrigerant and causing you harm. Just hook up the gauge... you can buy a refrigerant can with the gauge and hose hooked up to it.

[gale]

I was trying to avoid having to have the "a/c professionals" having to get involved. Will changing the pressure switch open up my refridgerant system?

Yes, swapping the switch will expose the innards to atmosphere. I'd try El Guapo's suggestion 1st. If you can measure the pressure that's in it now and verify it's not totally empty of refrigerant, then you can probably safely add a can to it. Best to slap a set of gauges on it to make sure it's not overfilled. Any car in the US manufactured after Jan 1993 will have R134a which is cheap and available just about anywhere without a license. You should have a label under the hood stating it's R134a.

If you find it's completely empty and has been at atmosphere for some time, then it's best to replace the receiver/dryer and pull a good vacuum on the system and fill it with X amount of pounds of refrigerant. Do a Google search & find out if you should add a token amount of Pag oil when putting in a new receiver/dryer. Do what Guapo suggested and put some dye in it as well.