Hey guys! I just got back from Mexico and the air was working beautifully as usual, but when I was within 10 miles or so from my house, it began to blow hot. After I unloaded my stuff, I popped the hood to find the compressor not locking at all, but after sliding the temp/thermostat switch back and forth, it started cycling on and off. I messed with it a little more and it kept going, the cycling stopped and it blew icicles again. It is obviously not low coolant because of that. Has anyone seen this? Could it just be a dirty contact? Has anyone tried taking it apart to clean it? And lastly, Is it available? It looks the same as thousands of cars I have seen (I have told myself a million times to stop exaggerating ). Any suggestions are greatly appreciated...Mark

 

Parts can be purchased from rock auto and autozone, the tricky part is to disassemble it while still on the truck but not impossible.

 

Mark,
This sounds like the dip relay inside the cycling switch is failing, this is how mine started, soon the ac would not run at all, try tapping the black box that contains the circuitry mounted on the expansion valve.

You also might have a relay on the fender depending on the year.

Jim

 

Thanks Exekial and Jim for the fast responses. I thought about my question and realized that the sliding switch does not do anything if the "max ac" button is pushed in, Is that correct? Jim, there is a block looking thing attacked to where the lines enter the cabin, is that the switch? Can it be replaced without blowing the charge? Is this what the sliding switch actually controls? Sorry for all the dumb questions. It is a 90 and this is between the R fender and the plastic fan motor case thingy...Mark

 

Mark,
Yes that it is the switch,
If this is the problem,

Yes the switch can be removed/ replaced without discharging the system, the thermistor probe slips into a well welded into the suction line and simply pulls out.

There should also be a low pressure cutout switch with 2 wires on the fender side of the block, make sure the wires are connected securely and not just hanging there.

https://www.dieseltruckresource.com/...-t112028.html?

Here is what the inside of the cycling switch looks like.





The inside selector switch provides a ground signal to the cycling switch that in-turn applies cycled signal to the clutch coil to prevent freeze up.

I know the dealer does not have them anymore but something might still be available online.

Depending on the humidity where you live, you might experience evap icing but here in SoCal it has happened maybe only once or twice, I had installed a thermostatic switch with a cap tube in my evaporator but it has never tripped the circuit and I still have freezing temperatures and I am low on charge.

Jim

 

Thanks Jim. I'll start my search for one. As far as humidity, I am in Phoenix, 'nuff said . The truth is though, that we get pretty humid in July and August, but right now we are living up to the old "but it's a dry heat" T-shirts. Thanks for the help...Mark

 

This is AC humidity!

http://i222.photobucket.com/albums/d...2A95E4CB64.mp4

 

Well, I set out on a search for this part and found exactly 1 place that has them, so in a very selfish way, I made sure to order mine, and then I will share the source BWAAAHAAHAA . He says that he has several more so go at it:

Thanks, Bob Schaetz @ East Texas Auto Air & Glass
1019 West Marshall Ave.,
Longview, Texas 75604
ph 903-753-0089
fax 903-753-0076
cel 903-720-1922

Part #E56-1101-016 It was 34 bucks plus 9 bucks shipping to Phoenix ...Mark

 

Man, that is a wet place, mine pees out about a pancake size leak, I can do without that type of humidity. There is a family from north BC that lives across the street from the house I am building in Mexico. When I asked them why they were year 'rounders in Kino, they said cold/bugs/humidity...'nuff said...Mark

 

Look at that tiny little iPod in the cycle switch!

 

I ordered one just now. Thanks for the hookup!

 

Amazing they can get 64 gb in there.

 

This is why the air is so important, took this shot from my TV of our LOW temp for the day. This is the difference between us and other hot places, that is A.M. by the way. Last August we had 9 straight days where we never got below 90, THAT is hot. We are looking at 118-119 today, the record is 118..Mark

 

The is my definition of hell. I am going way up in the rockies just so I can lay in the snow for a while. So for me, this kind of heat is way too much. When we were kids we went to tombstone to see them shooting an episode of "high chaparral" and it was 113. We could not stop drinking water. Manolito gave my little sister a kiss!

 

I have conditioned myself to like the heat, why not? I live here. That does not mean that I don't appreciate the cool temps. I climb a pretty tough mountain here everyday in the afternoon, yesterday my kestrel weather meter showed me 116 at around 1:30 P.M.. I think that it's healthy or nutty or both ...Mark