The A/C Amp Thread (1 Viewer)

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The resistor removal worked like a charm. I have a Dakota Digital tach signal generator tied into the original coil signal and it did not work. Clipped the resistor and the compressor fired right up.
 
how does one force their fj62 compressor to stay engaged longer? I see several pots on the fj60 board, is it possible to cut in a pot to get more cooling from the fj62 borad? that would in effect be altering the resistance signal from the thermistor to the board, right?
 
So if I'm reading this correctly... If I have a holley carb on my truck if I remove or cut the resistor shown the AC compressor will kick on at any rpm.

I have a Holley carb too and I'm considering cutting that resistor. I'm just worried that when my compressor kicks on, it will stall the engine out. Wish there was a way to have an AC idle up. How is your AC with the Holley carb?

I'm considering changing out to a Trollhole carb so I can have the Idle up.
 
how does one force their fj62 compressor to stay engaged longer? I see several pots on the fj60 board, is it possible to cut in a pot to get more cooling from the fj62 borad? that would in effect be altering the resistance signal from the thermistor to the board, right?

The only time the A/C amp on an FJ60 disables the compressor is during engine starts and if it senses the cooling evaporator temperature is at or near freezing, which would cause the coils to ice up (bad). If your compressor is cutting out it is likely due to the pressure switch, indicating low pressure in the system. Sounds like you need to have your freon charge checked.
 
We just charged it fresh with R12- I did NOT replace the pressure switch. it gets plenty cold, just not below 38.5...not really complaining, just wondering...
 
You can try adjusting the red potentiometer shown in post #5. As long as your evaporator doesn't start freezing the moisture in the air you should be okay.
 
We just charged it fresh with R12- I did NOT replace the pressure switch. it gets plenty cold, just not below 38.5...not really complaining, just wondering...

38.5 at the vent is pretty good. You won't get much colder without operating the evaporator below freezing.
 
that's what I wanted to hear!!! it is quite nice...this is the nicest mobile AC I've ever owned....
 
I don't see the a/c compressor stalling the engine or otherwise affecting the engine as long as the compressor cycles as appropriate. I don't think it would matter if the a/c were engaged at start or not. I assume most people turn their a/c off anyway prior to shutting the truck down, but in any case I don't see the a/c being an issue at start.
 
We just charged it fresh with R12- I did NOT replace the pressure switch. it gets plenty cold, just not below 38.5...not really complaining, just wondering...

a electric fan rigged to blow air through the condensor when a/c engaged is about the only thing that could improve that, and it would be a minor improvement.
 
You can try adjusting the red potentiometer shown in post #5. As long as your evaporator doesn't start freezing the moisture in the air you should be okay.
I was almost ready to open my system and replace my expansion valve when I found this thread. I adjusted the red dial and I am finally able to get the compressor to cycle long enough to bring it down to the temp I was looking for. I am running R12, so not having to open the system is awesome. So thank you very much for posting your info.:cheers:
 
Kinda the same question as before, but, is this the reason I'm not getting ac after doing a 2fe conversion?
 
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Kinda the same question as before, but, it's this the reason I'm not getting ac after doing a 2fe conversion?

Pretty hard to diagnosis a specific problem with so little information provided, but a realistic answer is a definite "maybe."
 
Rephrase: is cutting the resistor an essential step for working ac in a 2fe conversion in a 60?
 
Yeah the tach works, I have the stock one spliced into the 62 ignition
 
Hey TrickyT awesome thread! I have a Toyota AE86 and this thread really helped me out.
I am using an aftermarket ECU with COP so I couldn't get an RPM signal to the A/C Amplifier.
The board on my car is very similar.
I have attached a couple pics to show you and others.
I do have another question as I want my ECU to control my idle up. Will the A/C amplifier work with the VSV disconnected or do I need to insert a resistor to bypass that on the board too.

Thank you
Misery86
board.jpg
remove.jpg
 
Hey TrickyT awesome thread! I have a Toyota AE86 and this thread really helped me out.
I am using an aftermarket ECU with COP so I couldn't get an RPM signal to the A/C Amplifier.
The board on my car is very similar.
I have attached a couple pics to show you and others.
I do have another question as I want my ECU to control my idle up. Will the A/C amplifier work with the VSV disconnected or do I need to insert a resistor to bypass that on the board too.

Thank you
Misery86
View attachment 2214895View attachment 2214896
If your ecu idles up by getting +12v, then I would just wire up the compressor or vsv wire to the idle up input to the ecu. The board isn't smart enough to know what it's connected to, it just sends a signal when it deems appropriate
 
yes I was planning on just putting the compressor wire to the eco for idle up.
So if the VSV circuit is open circuit the amplifier should function with the pressure switch and the thermistor connected.
I just wanted to know if it would need anything in the VSV circuit.
 

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