Troubleshooting the A/C on my FJ60 (1 Viewer)

[pokerDawg]

My 60 is finally something I can drive everyday. The next thing for me to try and fix is the A/C. The PO said it used to work.

1. A/C does not light up when pressed.
2. A/C fuse under the dash is not blown
3. Fan works
4. A mechanic showed me the compressor still works when he gave power to the wire coming out of the compressor.

When I Google A/C FJ60 wiring diagram, too many random things show. Any leads would be appreciated.

 

[Aloha Jen]

You could try a different AC switch, they are usually only $10 for a used one to see if that fixes it.

Or unplug it and check to see if it’s getting power.

It’s not that expensive to get all new denso parts for the AC system, and not too hard pulling it all apart.

 

[pokerDawg]

So I found this diagram on MUD (of course). If anyone can give me any guidance, it would be appreciated. Thanks.

 

[Dindu Nuffin]

Does it even have refrigerant in the system?

 

[pokerDawg]

You could try a different AC switch, they are usually only $10 for a used one to see if that fixes it.

Thank you. Did you do a conversion to r134a with all those parts?

I guess I'll open up the dash this weekend.

 

[pokerDawg]

Does it even have refrigerant in the system?

I was assuming that the first step would be to have the AC button turn on the compressor like when the mechanic gave power to the compressor when he by passed the switch. Does it need refrigerant to simply turn on?

 

[3_puppies]

Does it even have refrigerant in the system?

this is important, there is a low preasure switch in the system, if the preasure is too low it will not turn the compressor on, it is there so you don't run the compressor dry.

 

[1972FJ55]

Like 3_puppies said, with low or no refrigerant the compressor won't engage. Before tearing the dash apart, hook up some gauges and see what the static pressure is in the system.

 

[Aloha Jen]

Thank you. Did you do a conversion to r134a with all those parts?

I guess I'll open up the dash this weekend.

Yes, converted to r134a because r12 is not readily available on my island. Plus, easier to trouble shoot problems with the system with the small inexpensive cans of r134a. Pretty straightforward conversion if you are changing out parts and putting new 134 compatible o-ring seals in. To get access to the AC controls, it’s just 5 or 6 screws to pop off the bezel and check the controller.

As others stated, the push button switch will not turn on the compressor if it’s not charged because of the low pressure cutoff switch.

Those are Beno’s Pictures, but I’m pretty sure that is the right part number for the pressure switch if you need a new one.
You could charge the system to see if the compressor goes on, but if it is empty now it is because of a leak. Best to find/fix the leak first, easy to do with the uv dye. We rented all the loner tools from autozone for free (manifold gauges, vacuum, dye injector, and uv test kit).

Just watched YouTube videos on how it all worked. My face looks more confident then I was, as I was pretty confused how it all worked in the beginning, but it’s pretty straightforward following the fsm AC troubleshooting section. Or just pay the AC experts to fix it fast if that’s easier. Either way, good luck!

 

[Deshet]

Was the system already converted to r134a? Did you have to vacuum everything out of the system? My AC turns on but it blows hot.

Does yours have power steering?

Thanks

 

[g-man]

If the compressor is old you prob need a new one. If you're replacing it, you should replace the dryer and condenser too. You need pag oil i believe about 5 to 7 oz. It goes in the compressor prior to you installing and filling with freon. Dump what ever oil is in the new compressor and put the right amount. Also you'll need 134 valves and replace your pressure switch and expansion valve pictured in the 3rd image. After you replace all that you need to rent a vacuum pump and run a vacuum on it for about 45 minutes. I believe Jen in the picture above is holding a manifold that hooks to the pump then to the in and out on the lines. Then when you go to fill it, you may find a leak so it may be worth a few extra bucks for dye so you can see where the leaks is.

Once you're ready to fill idle up the truck a little with the manual choke. The compressor will not kick on unless the amplifier tells it to. It usually is set to turn off the compressor at about 900 rpms so it's not running sitting at a street light. I'd idle up to about 1200 to 1500 rpms to make sure. There is a blue knob down under the dash that controls this but it's probably set right so don't mess with this right now. Once you start filling the compressor should kick on and you can hear it and see the clutch working. The system should take about 2 cans. You'll need to buy the 2 pack with a gauge included so you can see when you're full. If you want to see if your old compressor is not locked up you can unplug it at the black wire and jump to hot on the battery to see if it kicks on. This bypasses the low pressure switch. Just touch it for a sec or two to see if it moves the compressor.

 

[Dindu Nuffin]

I was assuming that the first step would be to have the AC button turn on the compressor like when the mechanic gave power to the compressor when he by passed the switch. Does it need refrigerant to simply turn on?

Yes, it does. There's a low pressure switch that prevents the compressor from coming on if there isn't enough refrigerant in the system. If you don't have gauges and don't frequently work on AC, and aren't looking for an excuse to go buy what will most likely be one time use tools, have a shop evacuate what, if any, is left and do a vacuum test to see if it holds vacuum. If it does, have them recharge it and enjoy. If it doesn't hold vacuum, then you can fire up Jen's parts cannon and go from there.

 

[ROFF]

You can bypass the pressure switch to see if it will turn on and run the compressor.

That would assume all other components are operating. If it turns on when bypassing the pressure switch you could be reasonable assured it’s low on refrigerant.

Feel around all of the fittings to see if there is evidence of any leaks.

I ended up with a bad expansion valve and just replaced the whole system.

 

[FJACS]

.... A mechanic showed me the compressor still works when he gave power to the wire coming out of the compressor.

He didn’t show you the compressor works - his test demonstrated that the electric clutch to engage the compressor works.

 

[mig79]

@pokerDawg ever get this sorted out?