Bad_Vision
Moderator
agreed.
A/C upgrade
- Thread starter GonOvr
- Start date
I don't have access to my FSM right now but does the stock switch run off of 12v power or does it complete a ground circuit?
Also, how does your thermo switch wire into the whole thing?
This is a learning curve for me. I'm somewhat of a newb when it comes to this particular stuff. I've been talking to my buddy google and other hot rod forums learning about ac's and wire harnesses for them.
I cannot for the life of me find a wiring diagram for a single or even a 3 or 4 wire ac compressor! Why would some ac compressors use 1 wire and others use 3 or 4 wires? I know one wire compressor is just a power for the mag clutch (simply an on/off) because the housing of the compressor would ground through the engine block. The 3 or 4 wires would be a power, ground, and then the others are some sort of safety interrupt?
Also, how does your thermo switch wire into the whole thing?
This is a learning curve for me. I'm somewhat of a newb when it comes to this particular stuff. I've been talking to my buddy google and other hot rod forums learning about ac's and wire harnesses for them.
I cannot for the life of me find a wiring diagram for a single or even a 3 or 4 wire ac compressor! Why would some ac compressors use 1 wire and others use 3 or 4 wires? I know one wire compressor is just a power for the mag clutch (simply an on/off) because the housing of the compressor would ground through the engine block. The 3 or 4 wires would be a power, ground, and then the others are some sort of safety interrupt?
Bad_Vision
Moderator
no idea i dont own a FSM for the 2nd gen. you made a good point if its a ground switch i may have to rework this idea.
GonOvr
New member
My factory switch is 12v switched not ground.
The thermo disc is placed on the accumulator. When it senses it too hot, it completes the circuit and vise versa. This way the compressor will only be on when the a/c switch is on and the accumulator is hot enough for the thermo disc.
looks like the factory compressor is a 1 wire as well. I will use our method, but i would like the compressor to cycle like it is supposed to. I am going to do some more digging and see what wire lights up for the orginal compressor. I will be spending this weekend putting my axle back and probing wires and cussing at wiring schematics.
Pins 85 and 86 can be switched between hot and ground. That doesn't matter really.
csrobb007
New member
Nate, I sent a message, but thought I'd drop it here too. Give these guys a call to see if they have a plug in harness with all the goodies you need...I've used them for alot of projects and have never failed to come through with direct plug in, no hack together stuff...worth a call...?
Painless Performance: The Official Home Page For The Best In Automotive and Diesel Performance Products
Painless Performance: The Official Home Page For The Best In Automotive and Diesel Performance Products
GonOvr
New member
OK after looking again, it may be even simpler.
If I run a wire from the A/C dual pressure switch to the A/C Amplifier (top right of schematic). I bypass the A/C cut relay. Since I no longer have a 3vz-e 4wd a/t, i dont think i need it. I still have the condenser fan relays installed, so they will fire but not send power to the fans (there are no fans anymore). I am going to try splicing a 5" piece of wire and get my B/W wire to light up.
If you dont hear from me, I set it on fire and I am watching it burn.
If I run a wire from the A/C dual pressure switch to the A/C Amplifier (top right of schematic). I bypass the A/C cut relay. Since I no longer have a 3vz-e 4wd a/t, i dont think i need it. I still have the condenser fan relays installed, so they will fire but not send power to the fans (there are no fans anymore). I am going to try splicing a 5" piece of wire and get my B/W wire to light up.
If you dont hear from me, I set it on fire and I am watching it burn.
Bad_Vision
Moderator
only problem i have with painless wiring is they will sell you what you can make for 10 times the cost
if you dont know wiring and you dont want to put effort into figuring it out then spend the 500$ for a rely all wired nice for your rig.
i looked at them for a TBI harness for my 4.3l swap they want 760$ for 15 feet of wire with connectors.
i can rip out the old harness and slim it down for 50$ ill go with the 50$
if you dont know wiring and you dont want to put effort into figuring it out then spend the 500$ for a rely all wired nice for your rig.
i looked at them for a TBI harness for my 4.3l swap they want 760$ for 15 feet of wire with connectors.
i can rip out the old harness and slim it down for 50$ ill go with the 50$
GonOvr
New member
Thanks man, but painless was a no go.
Bad_Vision
Moderator
Factory integration is the biggest mf'er of all time! Atleast record everything so we can watch the Toyota/GM bon fire on youtube
Nate just call it what it is a gmota:biggrin2:
