RTH: AC Issue (1 Viewer)

[Beams37]

Driving across country right now. Had AC charged and checked for leaks before I left. Been blowing VERY cold. Then, while stuck in traffic I turned it off and had the windows down. Now when back on, it’s NOT cold.

Fuse good … Sight glass full …

Any ideas I can check at next pit stop?

 

[yotadude520]

Verify that your A/C compressor is running, you'll hear the clutch engage when you press the A/C button. You can also get a test lamp and ensure that you're getting power to the spade connector that goes to the compressor when the switch is on.

If you're NOT getting power, you can bypass all the safety features of the A/C by running a cotter pin to a couple different pins. I'll have to read the A/C amp thread and try to remember which ones bypass the amplifier completely. Then you should have straight power to the compressor which can be verified with the test lamp. If this is the case you will need to turn off the compressor periodically so that it doesn't freeze.

If you ARE getting power and the compressor is cycling, then you might have experienced a sudden expansion valve failure which will eventually build enough pressure to burst a line.

If you're getting power to the compressor and it's not cycling, then you've got a dead compressor, even though I doubt that happened. My guess is it's something to do with the amplifier if it was that sudden.

Hope that helps!

 

[yotadude520]

To bypass the A/C amplifier, you need to jumper pins 3 & 7 by the way. Also make sure the spade connector to the compressor didn't become disconnected somehow.

Keep us posted!

 

[Beams37]

Thanks. I’ll check that at out next rest stop

 

[Beams37]

To bypass the A/C amplifier, you need to jumper pins 3 & 7 by the way. Also make sure the spade connector to the compressor didn't become disconnected somehow.

Keep us posted!

Ok. Stopped and did some looking. Everything connected. Compressor is clutching. My system inside has a hose going from fan to internal condenser box that was disconnected. Reconnected it. Going to drive a little more and see what happens.

 

[yotadude520]

Hmmm. Was the hose on the bottom of the box? That would’ve been the condensation drain for the evap. I’m not aware of any other hoses going from the fan to the evap box…

 

[cruisermatt]

You probably froze the evaporator. leave AC off for about an hour or two and then see if it comes back.

 

[Beams37]

Hmmm. Was the hose on the bottom of the box? That would’ve been the condensation drain for the evap. I’m not aware of any other hoses going from the fan to the evap box…

I’d have to show a picture.

I want to correct my previous post. I can visually see the clutch clutching. However, there’s no “clunk” like you would expect when the compressor kicks on.

Makes me think that maybe there is a slow leak that has caused the low pressure “valve” to prevent it from kicking on.

Thoughts ??

 

[Beams37]

You probably froze the evaporator. leave AC off for about an hour or two and then see if it comes back.

You’re referring to the one inside the cabin ??

 

[yotadude520]

I’d have to show a picture.

I want to correct my previous post. I can visually see the clutch clutching. However, there’s no “clunk” like you would expect when the compressor kicks on.

Makes me think that maybe there is a slow leak that has caused the low pressure “valve” to prevent it from kicking on.

Thoughts ??

I would think it'd be a very quick leak if it was blowing really cold one minute and not too cold the next - it would be worthwhile to confirm the freon levels with one of those quick gauges. Are you running R134a or R12?

The EVAP freezing definitely could happen if the thermistor circuit on the amplifier went bad, but you would've felt it get warm before you shut it off if that was the case.

 

[Beams37]

I would think it'd be a very quick leak if it was blowing really cold one minute and not too cold the next - it would be worthwhile to confirm the freon levels with one of those quick gauges. Are you running R134a or R12?

The EVAP freezing definitely could happen if the thermistor circuit on the amplifier went bad, but you would've felt it get warm before you shut it off if that was the case.

I'm running 134.

I may not have described it well originally. We left Nashville this morning and it was blowing cold. Around Little Rock, I turned it off and rolled the windows down while we sat in traffic for about 30 minutes. When we got going again, the AC was just not blowing cold at all (cooler to have windows down).

I found a shop here in OKC that is going to check the Freon levels in the morning. I'm hoping it's just low Freon that is preventing the compressor from engaging.

We've had s*** weather, so haven't been able to do much trouble shooting. I'll gladly accept any additional troubleshooting ideas and I'll provide an update tomorrow after I leave the shop. I may have to suck it up until I get to Phoenix.

 

[DrRock]

If you are running r134a I’d just fo to the local parts store and pick up one of those recharge kits that come with the gage. Also, if the system is empty of coolant, there is a safety switch that won’t let you turn on the AC if no pressure is in the system. When you depress the AC button, does the light come on? If no, then your system is empty, if yes, then you might just need a top off.

Good luck!

Cheers, James

 

[Beams37]

If you are running r134a I’d just fo to the local parts store and pick up one of those recharge kits that come with the gage. Also, if the system is empty of coolant, there is a safety switch that won’t let you turn on the AC if no pressure is in the system. When you depress the AC button, does the light come on? If no, then your system is empty, if yes, then you might just need a top off.

Good luck!

Cheers, James

The light does come on, but air not cool.

 

[Beams37]

Ok. So I found an awesome shop in downtown OKC. They put in a pound of Freon, so there’s a leak somewhere. Even with the dye from the fill up last week, he couldn’t see a leak. We think it’s leaking on the interior side of the system. Hoping this makes it for the next 2 days. Lol

 

[duncanrm]

Ok. So I found an awesome shop in downtown OKC. They put in a pound of Freon, so there’s a leak somewhere. Even with the dye from the fill up last week, he couldn’t see a leak. We think it’s leaking on the interior side of the system. Hoping this makes it for the next 2 days. Lol

A good shop will have a hydrogen trace gas and wand for leak detection.. thankfully the evaporator and TX valve in the 60 are reasonably straight forward to get to for repair if it does turn out to be that.

 

[Beams37]

A good shop will have a hydrogen trace gas and wand for leak detection.. thankfully the evaporator and TX valve in the 60 are reasonably straight forward to get to for repair if it does turn out to be that.

Yeah. The guy at the shop basically said “the right thing to do would be to track down the leak with nitrogen, but you don’t have time for that”. LOL

It’s holding so far, but I will get a shop to track it down when I get to Phoenix. Since we could find any trace of the UV dye in the engine bay, I think it’s inside around the evaporator.

It’s been cold all day, so hoping it holds for one more day.

Thanks to everyone for the advice and ideas.

 

[Beams37]

Made it to Phoenix today. It was fading fast the last few hours. Will jump into the local clubhouse and look for a shop to help me track down the leak.