AC was working this morning, been using company van today, get back tonight and now it will not cool. The AC clutch does not appear to be engaging. I checked the 10 amp fuse in the PDC under the hood and switched a relay (the wiper motor relay) and still nothing.

What should I look at next, or is it done?

 

Low pressure switch could be open, keeping the compressor clutch from engaging. Check to see if you still have a charge of refrigerant... (low side pressure greater than ~35+ psig.) If less, you may have developed a big leak and dumped your refrigerant charge! Bummer...


If OK(~60-90+psig) then check the low pressure switch by temporarily jumping the 2 plug wires to tell the computer: Pressure is "good", ok to engage compressor.
CLutch should engage.

 

well my compressor locked up today. where is a good place to buy one being they areto the diesel im told by the parts store. whats the best way to test my system cause i had a leak but couldnt find it, well it let me know today the compressor was bad LOL used a non ac belt to get to work for tomorrow. how much can i do my self.one guy told me i have to put in a new dryer and other things to make sure the system is clean. drop me a line at par12730@sbcglobal.net thanks phil

 

Was low on refrigerant. Got it recharged, now to see how long it lasts.

 

Ok, so it definitely is leaking somewhere. Put some dye in it and have not found where it is leaking so far. I am thinking the evaporator. Not going to be a fun project. Looks like you have to drain the anti-freeze as well. If that is definitely what is going on I guess I will be replacing the heater core while I am at it. Any other thoughts?

 

Just pinch off the heater lines before disconnecting and you won't have to drain the cooling system.

 

no need to pinch the heater lines of drain the cooling system..been there done that..twice!! just make sure the blend door motor and door are connected before putting it all back together..
yes you have to move the dash out of the way or out all together..your choice.
the HVAC box must come out! yes its a Pain....
just make sure the blend door and motor are connected.
you might want to look close at the heater core while you inthere..and replace if needed..

if you've added UV dye..check the evaporator drain for dye..if you have any you've found your leak.this is how I found mine..

-dkenny

 

Got it out and replaced the heater core and evaporator core today. Not too terribly bad, a little bit of a PITA, but I have had worse. Just glad to finally have it behind me. Now all I have to do is recharge the system and hopefully will be good to go.

 

Anybody know the capacity of the r134a for the 2001? I thought I had put enough in it, but the compressor is cycling on and off. Filled it yesterday morning and it is still cold, but just hoping I don't have a leak somewhere else. I probably put about 28ozs in it.

 

Perhaps you should download the FSM???? It has lots of information.

 

Where can I find the FSM?