Jlara6898

I just purchased a 1993 toyota pickup and everything look fine with the A/C system but whenever I turn on the fan blower I notice that the A/C compressor engages then I have to push the A/C bottom in order to turn on the idle up valve and get the rpm higher. So now if I turn on the fan blower the A/C compressor clutch engages and if I turn the blower off it will disengage the compressor clutch.
help!!

maxvp01

I am a little confused on what your asking. But turning just the fan blower on shouldn't engage the compressor. During the winter you use just the blower to move heat throughout your cab, your compressor should not be engaged during then.

The AC button is used to engage the compressor (and electric fans if equipped), the compressor will then disengage when it’s hit a certain pressure, then engage again once it’s hit the other pressure.

If you are cooling your car with the AC with the AC button on, and the fan blower on, and let’s say you turn the fan blower off, the compressor should disengage because your no longer calling for cooling. Even though the AC button is pressed, the compressor will be disengaged until you turn the fan blower back on

If you are just using the fan blower, without the AC button pressed, the compressor should be disengaged.

Hopefully this helps, your original post was a little confusing to read, but I think it sounds like it’s working properly. Has the car ever had any work done to the wires in it?

Jlara6898

That's the thing even if I leave the A/C bottom off and I just turn on the blower fan it engages the AC compressor.

Jlara6898

That's the thing even if I leave the A/C bottom off and I just turn on the blower fan it engages the AC compressor.

2ToyGuy

Sounds like the AC button is stuck ON, or shorted out. You can open it the center console, and pull one of the wires off, and see if it still does it. That will tell you the tale of the switch's condition.
If it never turns the compressor off, also, it sounds like the pressure switch may have gone south on you as well.
I've not done a lot of work (any) on my AC systems. When I moved up to Oregon from Yuma, I pulled the belts off the compressor in both my 87's, and haven't used them since. Didn't see any point. It gets up into the 90's here, which in Yuma, where I lived almost 30 years, that's a nice evening temp. I just use the 2/55 AC system, now. 2Windows, 55 MPH. Works fine for us

Good luck, and hope you find the trouble. Let us know what happens!
Pat☺

maxvp01

I was able to check into my 1989 Toyota Pickup FSM and here is the diagram for the system. The highlighted picture is the same picture just highlighted for the 3VZE and 22RE motors.

I think Pat is onto something with the AC switch, and the pressure switch.

You mentioned if you leave the switch off, and activate the blower, the compressor engages. According to the diagram the only thing that blower wire goes through is the AC switch. Looks like it may be stuck closed.

This is how I would test it:

-turn the truck on and confirm the compressor is still engaging with AC switch off, blower on

-then turn truck off, pop the AC switch out (it just pushes in)

-with AC switch popped out and out of the circuit turn the truck on and perform the same test to see what happens.

this seems like it would it “open” the circuit to simulate the AC switch in the off position

Jlara6898

Ok I will be trying that tomorrow or on the weekend. Other thing that I will like to ask you guys think is Nirmal for the 10A fuse of the ac compressor, to just have 1 cable going into it no other cable goes out the fuse just one?

maxvp01

Yeah I think my compressor is one wire as well. Wiring diagram also shows one wire going to it. The compressor is probably grounded by the engine block.

Jlara6898

Yeah I just notice that is one wire as well the ground is connected to the body of the compressor itself. So for what you mention about the ac switch to be stuck open I don't think so because when I turn on the blower and the ac compressor engages I need to turn on the ac switch right away in order for the AC idle up to kick on and keep the idle higher for the drag of rpms that the compressor develops.