UpInSm0kE

The A/C has not worked since I bought the truck about a year ago and I want to figure out why the compressor is not coming on before the summer hits. I have not been able to find any threads on this but if there is I apologize. When I hit the A/C button it lights up but the compressor does not kick on. The belt is hooked up and is in good shape. Could the A/C System be low on Freon? Is there any in-line fuses that need to be checked for this to work? Thanks in Advance

abecedarian

Definitely could be low on freon. There should be a low pressure as well as a high pressure switch on the system and if the pressure is too low (read: as in no freon) the system will not kick on.
You could try charging the system yourself (may have to convert to 134a if it's still set up for r12) and see how that goes but if it's that low on refrigerant it probably has a leak and you should take it to a shop for diagnosis.

SoCalR6

Just a thought but is your power steering leaking? Prior owner of my 94 3vze runner had a ps leak for years. Appears they removed the belts from the a/c pullies because the leaking ps fluid fried the a/c clutch and froze it. New remanufac compressor and pullies/belt and I now have a/c

UpInSm0kE

Ok thanks for the info. Are there any fuses or relays that complete the circuit that could be shot?

turborich

Do you have a set of Gauges you can hook up to it? What year is the truck? 134a or r-12? If you have the sight glass on top of the filter/dryer behind your grille then go ahead & jump the compressor to + on the battery & look at the sight glass. If there are lots of bubbles in it then it's low. Don't leave it jumped like this too long.

I am guessing that it's just low & you need more refrigerant to turn the compressor on. If it is low make sure to add a bit of the proper oil into the system as well.

UpInSm0kE

Turbo thanks for the input I have a 93 yota PU 4x4 22RE with 245K. I will try the sight glass technique that you have mentioned. I don't have any gauges to hook up to the system.

DeathCougar

iTrader: (23)

Quick way to test the compressor clutch is to unhook the plug leading to it, hook positive power to that, and negative power to the block (for the ground) and the clutch should engage.

If it does engage, its working properly. With the light coming on, that tells me the system itself is functioning, but its out of Freon. If that is the case, you need to find the leak first, fix that, and then have it refilled or you will be having this problem again in a few days/weeks.

turborich

93 so I'm guessing that it's r-12? It could be 134a as well though as 94 was the cut off year for r-12. Just look at your fittings, are they quick connects (134a) or do they look like tire valves (r-12)

134a can be purchased just about anywhere for between 7-12 bucks, r-12 is a bit harder to find & you need to be licenced to purchase it. You could always retrofit it to 134a if you really wanted to.

let us know what system it is. Also check for oil residue near the compressor, hoses & fittings. this will likely be a leak. some leaks may take several months to leak out while others may only take days.

DeathCougar

iTrader: (23)

1993 will be R12, unless it has been converted.

R12 has external threads on the fittings, R134A has internal threads on the fittings.

arizonaguy

just convert it to 134a