Manual a/c amplifier pinout one connector

https://youtu.be/yaE6uiLjqYI?si=D0O6VjwGFiwQ-mpP
Guys saying about 1 to 1 relationship psi to ambient temp @ avout 16:30 any validity to that or is it maker specific? If that's right then my low pressure switch could be kicking out my compressor right?

 

Thank you sir!

 

My last Toyo was an 1988 with r12 refrigerant. I’m not yet familiar with the newer Toyo a/c’s. I will guess it has no filter dryer, but maybe an accumulator canister that stores extra refrigerant. If you put the system under a deep vacuum for a couple of hours it will remove any residual moisture.

Your system should hold somewhere around 19 ozs of refrigerant. Maybe more, maybe less. You have a sticker under the hood that will tell you the amount. Even if you put only one 16 oz can in, your high side pressure would be way higher than it is. And the compressor will engage but will short cycle (on and off).

Did you fill the system using the low pressure side port with engine and a/c running ?

 

I have not read all of this thread or watched any videos in them. I’m a Johnnie come lately.

At a constant temperature, different refrigerants will have different known pressures. So essentially, you can determine refrigerant type, by its pressure.

I hesitate to tell you what I would do because you may not feel comfortable troubleshooting the system and as you know the engine compartment is a dangerous work area.
But here goes, if you suspect a bad low pressure switch, a jumper wire at the switch disconnect will complete the circuit. If the compressor energizes, immediately remove the jumper. Limit switches “rarely “ fail.

If you suspect a faulty compressor and/or clutch, disconnect the compressor electrical connector and put 12 volts to the spade on the compressor. Beware, don’t let the 12 volt wire touch any other metal.

If nothing else, you may understand the system operation a little better.

 

Another misprint by Toyota. It says the truck uses R1234yF. Then in the instructions it says to charge it with R134a.

When I have a A/C issue, I look for obvious signs of damage, hole in condenser, bad clutch, noise from compressor. I then evacuate the system to see if there was any refrigerant in the system, I then put it in a vacuum for a couple minutes (yes, I know 10 minutes is recommended), then I charge it to the correct amount using the decal under the hood. It tells you what type of refrigerant and the amount.

I haven't used a gauge set in like 20 years. The machines make it so much easier.

 

I jumped compressor relay and magnetic clutch engaged

 

Yes sir charged low side with a can from parts store which from what I hear is a gamble cause it probably has sealant in it. While running with a/c max. I doubt accumulator I'm pretty sure I see place for drier filter built into condenser housing. I just don't know anything about 1234yf if components have changed or what.

 

How do you get access to the machines?

 

Want to confirm I have manual controls I'd call it manual as I can't set a degree setting I only turn wheels to desired setting. Also can gauge shows 50 psi to be full thinking this isn't definite proof of recommended pressures but a good guide

 

There's no way to determine charge level based on static pressure readings, as a guide with 134a and 1234yf static pressure in psi should roughly equal ambient air temperature in degrees F (actual temperature/pressure relationship is on most A/C gauges). If it's much below that the system is basically empty, if it's at or above that pressure there's at least some charge in the system.

If there's a very low charge of refrigerant in the system it's not going to allow the compressor to stay on to avoid damaging the compressor.

 

There is absolutely no way to check a charge using guages without engine and a/c running. There are only 2 ways to get the correct charge. Weigh it in on a $300 scale or find refrigerant cans with the proper amount . It’s perfectly ok to have a lower charge. It is very bad to overcharge. Most of us can get near the full charge with engine running and a/c on full blast. It isn’t exact, but close enough.

If you pull the electrical connector from the compressor, check for power on the connector while engine is running and a/c is on full blast and on lowest temperature setting. If you have 12 volts then you have a bad compressor

 

This test will not work on Toyota's that use a compressor lock sensor because when the A/C Amplifier commands the compressor clutch on it expects to see a lock sensor signal, if it does not see a signal within a few seconds of commanding the clutch on it will shut down the clutch circuit and flash the A/C light. So if we don't have a flashing A/C light most likely the clutch is fine.

 

System recovered. These images are gauges during vacuum with pump still engaged apprx 25 mins in going to let run for 45 min turn off see if vacuum holds will update

 

Inspected Schrader valves o rings I'm good condition and stems bounce back when depressed

 

1hr vacuum pump running

 

Pump off 30 mins

 

1hr after pump off

 

Seems as if increasing engine speed 1500 to 2000rpm keeps compressor running a little longer and a/c is cold when compressor engaged

 

Increase above that range no effect

 

Lmfao just messing around I blipped over and over again throttle and it kept compressor and a/c light on till I stopped and it cut the light off I think I need a compressor