A/C Amplifier wiring (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Dec 31, 2009
Threads
30
Messages
571
Location
Tucson
Does anyone have a wiring diagram for the FJ60 ac amplifier? I am trying to wire around my ac amplifier and need to know what color wires go to what and my chasis manual is dated 1980 and it doesn't show anything regarding this little item.

Thanks,

Don
 
If you're trying to bypass it because it's broken, buy a used one from SOR (I know, it's $$$). I tried the rewire method and all it does is keep the A/C compressor running constantly when you have the A/C on and it freezes up the system. But if your doing it for another reason, nevermind :p
 
gsdog2,

Thanks for the tip but I have converted to diesel and need to bypass this silly box to get my ac to work. I am going to keep my thermal switch and low pressure switch in my bypass so that I don't do what you did with the freezing up problem.

I just need to know what each wire is so that I can accomplish this.

Thanks,

Don
 
hope the conversion is going well, Don. please post up any findings! Also if you get the chance can you send me some pics of your AC set up and lines?

thanks

clint
 
Hi Clint,

I will definitely send you some photos when I get this all worked out. I ended up going with a Sanden 508 compressor so I could clear the steering box and then I had to build all new lines. I have it all working but only with the compressor wire jumped to the battery. I am using an ABS sensor on my harmonic balancer for the tach signal on the factory tach and it works but apparently the signal isn't right for the ac amplifier to work so that is why I am now trying to wire around it with a relay system. When I get this worked out, I will detail how I did it for you.

I still need the schematic for the AC amplifier if anyone has it?

Thanks,
Don
 
Last edited:
ABS sensor if it has a magnet , this impulse type won't have enough juice / power for the amp to see it. If the sensor (abs) hasn't got a magnet , then that's a hall effect , and it will never work , due to it must be driven.

Since your trying to bypass the control of this , why not use a temp evap controller . Many early Euro cars used this on the FLM and expansion valves systems. name a euro maker you know , and ill tell you a model that used one.
The AC amp also took in the running RPM from a FJ . You would no longer need that due to a governor .

VT
 
VT,

My ABS sensor is a magnet type and your right, it doesn't have the juice to work with the ac amp from what I can tell.

Enlighten me on how the temp evap controller works.

The FJ60 has a thermistor or freeze switch on the evaporator right now as well as a low pressure switch to safeguard the system. I was thinking about using these incorporated with a relay for my own ac control system. Hence the need for this post and the need for the wiring diagram of the ac amplifier.

Any help is appreciated very much.

Thanks,

Don
 
Well any type of switch I have seen on mine were (now Im not looking at it, but from last year memory ) they were max limiters , so if it got over pressure , then it would open a circuit(or close, didn't look into it YET) I'll have a look @ my evaporator tomorrow and update my thinking before I go off kilter.

temp evap controller works with a capillary tube that is set to open a adjustable switch (you control the temp setting) . When the evap is at max cold , then the switch opens the AC compressor, But if something fails the over pressure or any other safety system overrides the feed to the temp evap controller.

I have no idea if any Asian or Domestic cars used this. Im euro from dirt, this is the first non-euro car i have owned or studied. BMW 2002 1970s used this , Audi fox , VW also , last years i believe i remeber them in were 200 series Volvos till 90's . Ill see if I can get a pix to post.

VT

Edit , second switch area from left :
pg24.jpg

ThumbnailLarge.ashx
 
VT,

I like your idea on this and I think it would work with my relay setup that I am working on. So where does the capillary tube go? Does it wrap around the evaporator or go inside the ductwork just after the evaporator?

This would give me some adjustability to how long the compressor stays on in relation to the temps in the evaporator, right?

Don
 
Last edited:
Here is the internal diagram of a 62 amp, the function is a little different from the 60 as to where it gets the signals from.
(note the name on the drawing, not mine, generously provided by Tom)

The best approach that I found in your situation was to actually just get an FJ62 amp since it functions exactly the same way, it is plug and play and the only difference is that it gets a signal from the ecu rather than the coil to tell it the truck is running. The only down side of the 62 amp is that when wired into your conversion the compressor can engage as soon as the key is on and then your starter motor has to work harder, easy to get around if you just get in the habit of turning off your AC button when you turn off the truck.

I've done a lot of typing on this over the years, I think these are some of the more pertinent topics that apply to your problem, take a look at my posts there if this doesn't make sense.

KR


https://forum.ih8mud.com/60-series-wagons/173016-explain-what-ac-amplifier-does.html

https://forum.ih8mud.com/60-series-wagons/235481-ac-control-box-bypass.html

https://forum.ih8mud.com/60-series-wagons/227086-c-question.html

And here is a summation of my application:
https://forum.ih8mud.com/diesel-tec...78-my-2f-1hz-t-swap-thread-9.html#post2346351


Pic:
FJ62-ACamplifier.jpg
 
Last edited:
VT,

I like your idea on this and I think it would work with my relay setup that I am working on. So where does the capillary tube go? Does it wrap around the evaporator or go inside the ductwork just after the evaporator?
Don
Let me look into this again , I believe it was defiantly inside the evap and on a tube , but where in proximity of the expansion valve ,that is where i need to check. My manuals I will see later , Im mobile & should be back tonight .

This would give me some adjustability to how long the compressor stays on in relation to the temps in the evaporator, right?

Don

Correct , and there is a micro adjustments to trim out the cycling ..I am still going to have safety's and timer delays installed. Must have some blower speed, compressor hi temp , high side receiver drier over pressure switch , freeze up sensor, Delay on Compressor start after 15 seconds of alt charging/ and no charge , compressor cuts.
This is nothing new , normal euro early style say 75-1990 ..

I am not going to use the Amp , but maybe some sensors it uses. KISS system.

VT


Now that Mr Kevin Rowland posted , he reminded me of a question for him.
GEAR SHIFT LOCK !! got one to sell ?

VT
 

Don,
This is commonly referred to as an a/c thermostat. I didn't think of this as an alternative when we spoke the other day, but I think it would do the job. The probe goes into the fins of the evaporator core and the electrical connection goes inline on the hot wire to the compressor. We carry a few varieties of these in stock, so if you want to go this route, let me know.
Rex
 
I checked the manuals . dusty books , good to see the old stuff, I can spell most of those words.

It is to be mounted internally in the fins and then the end is to be mounted 1/2 way the way on the tubes flow , so mid flow. Now MY Manuals have huge print to use lead foil and cork tape for stopping copper to aluminum electrolysis on the evap from the copper, and the cork tape is to stop vibration and loss of heat.

Checking this is freezer time and a DVM, Basic and straight forward.

I also had a note from Wayyyyy Back that if you tried to
"tin " the capillary tube, the heat to apply the solder would kill the capillary tube waxes.

VT
 
Alright guys, I got it fixed and it is running great!

A huge thanks to VTCDN on this one. I went down to the bone yard and found a couple of these out ot mid 80's Volvos and they work perfectly. I mounted it in front of the Evaporator and put the control in the left spare switch hole next to the ashtray and it looks pretty close to factory. It is nice in that I can adjust how much I want the compressor to cycle and it adjusts temperature as a result.

This is a very simple system and solved my problem for $10. Ultimately I will find an FJ62 or HJ61 amplifier to solve this, but for now I have A/C!

Thanks a bunch guys for helping on this. I really appreciate it.

Don
 
Your well on your way if you have a diesel & governor . The AMP is for AC & engine control of fast idle or so it won't stall due to extra load from the compressor. There mid 80's euro / volvo had an idle compensated for when the compressor cut in, but because euro carbs / fuel injection was always a MASS velocity system , Most had NO idea of how the idle was maintained thru vacuum porting.

Make sure your system has the basics of protection i posted.

One of my vehicles can run for hours with the ac on @ high idle keeping the inside temp close to 15c /68 f while I needed to do my work . Life & dog waited in comfort with no problems.

Glad your on your way Mr Don.

VT

Edit add, Mr Kevin, thanks , got one coming.
 

Users who are viewing this thread

Back
Top Bottom