Hello Everyone. So I have another issue this time being the AC. About a month a go I recharged the system got the AC blowing cold and working fine. I stopped using it because it was still chili out so I just rolled down the windows. last week I turned on the AC and nothing happened. So I thought maybe I should take it to a local shop and have it professionally recharged. They recharged it the right way and still the Compressor wouldn't kick on. He took off the relay and jumped it directly and it turned on and cold air started blowing out. He said the AC climate control box may be bad. I bought a new relay and still nothing. Any advice you guys can give me? Can it be the AC climate control box that is bad? Thanks

 

Cool air would still blow out if there was refrigerant in the system, but it was low. You should check for a leak - the system has a low pressure switch that cuts off power to the compressor.

If I had to bet - I'd hate to say it, but it's probably the evaporator. Pain in the *** to fix, and expensive to do at the shop, but you could DIY for +/- 8 hours and about $100.

 

Thanks for your response but the thing is when I took it to the shop they recharged it to the correct spec and the AC clutch would still not engage. So what the Tech did was remove the AC clutch Relay and jumped it directly and then the AC clutch engaged and cold air started coming out.

 

There's a possibility that the Low Pressure Cyling Switch on top of the AC Accumulator is bad. This switch is normally open and when the pressure in the system gets high enough the switch will close, enabling the compressor clutch and aux fan.

What that tech should have done was remove the connector from the Low Pressure switch and jumper it and see if the clutch engages.

You can do this. Here's a pic that shows the switch being jumpered. Use a small paperclip. If the paperclip doesn't fit try hammering the ends to flatten them out then retry. Do not shove the paperclip into the pin sockets if they won't go in easily.

Give it a try.

 

Probably should have also asked you - when you recharged the refrigerant the first time, was it to the appropriate pressure? And when you took it in the second time, did they just add refrigerant, or evacuate and re-fill?

Hopefully it's just the pressure switch. If not, I'd start looking at other underlying causes such as leaks.

 

Thanks, I'm going to try this right now.

 

Forgot to mention earlier that after you jump the connector the engine must be running to get the fan to run.

 

Well I tried that and nothing happened. Turned the engine on, AC on and nothing. I think I have a leak on the LOW servicing port. I unscrewed the cap and heard a ( Pssst ) come out from it and there was freon bubbling. Maybe the valve is loose ( not sure how those work). So I am guessing nothing happened cause its low on freon.

 

Jumping the Low Pressure Switch bypasses the switch altogether. The Freon could be zero pressure and it should still activate the compressor and fan....except that.....the High Pressure switch is wired in series with the Low Pressure Switch and if it's open (Normally Closed) it will break the circuit. Try jumping the High Pressure Switch and the Low Pressure Switch at the same time. The High Pressure Switch is that switch in the pipe close to the compressor (see pic below).

Looks like the valve in the servicing port is loose or has a bad seal causing the Pssst and bubbles. You'll eventually lose all the freon through that leak. You could try to tighten the valve with a tire air valve tool. I did this on my POS 2000 T&C.

 

Alright I will try jumping both switches and see if that does it.

 

So I tried that and nothing happened again. What I did notice was that once the paper clips were in the engine speed decreased and if I removed either one of the paper clips the engine speed would increase. Like if there was a load when both paper clips were in both connectors.

 

What expectations do you have? What do you expect to happen?

Was the clutch pulling in?

The compressor engaged will will dip the RPM until the IAC picks it up.

 

I have never worked on an AC system before. I just know it was working well until I tried again and nothing happened. The AC clutch did not engage nor did the fan.

 

Does your AC/Heater blower work?

 

Take your doors off. Problem solved.