AC stopped working, only blows hot

[Jeep&dogs]

Anyone have this issue? It was working fine last week, drove it today and it’s like the heater is on. I checked the fuses, the system seems charged. I tried it again when I got to where I was going and it started blowing cold, turned the jeep off, came back out 20 minutes later and nothing, ac compressor won’t kick on, fans it’s blowing nothing but hot air…….

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[Mtpockets]

Do you hear a “swooshing“ noise in your dash? My ‘16 Rubi is low on refrigerant when I hear that noise and it blows hot.

 

[WhereRU_A-A-Ron]

My previous vehicle had an issue where the fan would intermittently fail to work. It was difficult to identify because it didn’t always happen and I would always get cold AC unless I was stopped. Eventually found out that the relay for my fan was failing and causing the fan to not run sometimes. I wouldn’t notice it while driving because there was sufficient air movement to exchange heat.

TLDR: could be something simple that’s causing your fan to not run so you’re not exchanging heat. Still under warranty?

 

[Jeep&dogs]

It’s a 2020 so it’s still under warranty. Blower fan inside the Jeep is working fine, it doesn’t seem like the AC compressor is kicking on. You can usually hear it kick in and when you put it on Max the cooling fan usually kicks in almost instantly and that’s not coming on either. I absolutely hate bringing the thing into the dealer.

 

[Carolina Jeeper]

Maybe you will get lucky and its a simple fuse or switch failure

This sounds like a engine cooling fan not functioning correctly. The high side pressure of the AC system will rise and then the engine cooling fan should be switched on to draw cooler air through the condenser and in turn lowers the high side pressure. Similarly to what was already stated, IF the vehicle is moving fast enough it may not become apparent that there is an issue until you slow down and stop moving. Then you will feel the warm air blowing since the system cannot function as it should exchanging heat. System pressure builds and then eventually no compressor operation.

On a warm humid day you want fan blowing a lot at a vehicle standstill or the AC system will cease to cool the cabin air. The compressor will not cycle on and off as it should normally. It will remain off for extended periods of time and then only remain on for very short amounts of time.

One trouble-shooting method that can be done is to use a decent fan to blow air into the grill while the engine is running and vehicle in park. Run the AC and see if the problem seems to go away. Should be able to hear the loud JL engine cooling fans if they are working before having to do this anyway.

Warranty covered repair for sure no matter what the cause of this failure is barring damage from something.

 

[Jeep&dogs]

Maybe you will get lucky and its a simple fuse or switch failure

This sounds like a engine cooling fan not functioning correctly. The high side pressure of the AC system will rise and then the engine cooling fan should be switched on to draw cooler air through the condenser and in turn lowers the high side pressure. Similarly to what was already stated, IF the vehicle is moving fast enough it may not become apparent that there is an issue until you slow down and stop moving. Then you will feel the warm air blowing since the system cannot function as it should exchanging heat. System pressure builds and then eventually no compressor operation.

On a warm humid day you want fan blowing a lot at a vehicle standstill or the AC system will cease to cool the cabin air. The compressor will not cycle on and off as it should normally. It will remain off for extended periods of time and then only remain on for very short amounts of time.

One trouble-shooting method that can be done is to use a decent fan to blow air into the grill while the engine is running and vehicle in park. Run the AC and see if the problem seems to go away. Should be able to hear the loud JL engine cooling fans if they are working before having to do this anyway.

Warranty covered repair for sure no matter what the cause of this failure is barring damage from something.

Its definitely not kicking in the AC clutch on the compressor. When you set it on MAX it should kick the cooling fan on high regardless of the coolant temp and it doesn’t do that either. The High side line is not hot to the touch, I haven’t put a gauge on it so I don’t know what the pressure is, I looked around and I didn’t see a high pressure switch anywhere but I’m not sure if it’s built into the compressor on the Jl. When you pull the AC clutch relay and put it back in you can hear the clutch kick in momentarily and then kicks back out. I know it will be warranted but I absolutely hate having the dealer touch anything. And it’s a pain to pull the cables out of the security module to remove the tazer.

 

[JeepCares]

It’s a 2020 so it’s still under warranty. Blower fan inside the Jeep is working fine, it doesn’t seem like the AC compressor is kicking on. You can usually hear it kick in and when you put it on Max the cooling fan usually kicks in almost instantly and that’s not coming on either. I absolutely hate bringing the thing into the dealer.

We understand your hesitation to visit the dealer, Jeep&dogs. However, if you choose to, we can certainly provide an additional layer of assistance while there. We're in private message to discuss!

Kate
Jeep Cares

 

[WranglerMan]

As stated if the AC clutch is not engaging it wont work correctly, you should hear the clutch and pressure switch cycling when it’s running and the large suction line should be cold and sweating.

 

[Jeep&dogs]

It has to be something electrical or computer related. I drove it again today and it worked fine. Shut the Jeep off and came back out and nothing.

 

[Jeep&dogs]

Also the controls on the radio now only show Hi/low. It doesn’t scroll through the temperature like it always did.

 

[Carolina Jeeper]

Its definitely not kicking in the AC clutch on the compressor. When you set it on MAX it should kick the cooling fan on high regardless of the coolant temp and it doesn’t do that either. The High side line is not hot to the touch, I haven’t put a gauge on it so I don’t know what the pressure is, I looked around and I didn’t see a high pressure switch anywhere but I’m not sure if it’s built into the compressor on the Jl. When you pull the AC clutch relay and put it back in you can hear the clutch kick in momentarily and then kicks back out. I know it will be warranted but I absolutely hate having the dealer touch anything. And it’s a pain to pull the cables out of the security module to remove the tazer.

Yeah, looks like more than an engine cooling fan issue. There are CANBUS faults that cause and AC compressor to not engage. Most if not all have terminating resistors on the CANBUS that when one fails, things like the AC don't function. There are soooo many things that could be wrong here.

 

[Jeep&dogs]

It’s definitely something electronic. Just pulled the top and doors off. When I started it to pull into the garage the AC kicked in and the cooling fan, it was blowing cold. Turned it off, pulled everything, started it up and pulled it back out of the shop…..ice cold AC. Parked it in the drive, started it up about 10 minutes later….melt your skin hot. Something is not telling something to turn on.

 

[Jeep&dogs]

Well it goes in Wednesday, guess we will see what they have to say about it. It actually worked all day Saturday and Sunday but it was a little cooler out. I drove it today and it worked when I pulled out of the garage. It sat in the sun for a few hours and got hot and it would not come back on. I actually stopped by the dealer today to see if they could take a quick look while it WAS NOT working but they pretty much refused to look at it. I mean why on earth would you want to look at an intermittent electrical problem when it’s actually NOT working. Anyone want to take bets that when I drop it off Wednesday they tell me “they couldn’t duplicate the problem” so they couldn’t diagnose it?

 

[m3lover1]

Hey OP did you ever figure out what when wrong? Mine just started to do the same. Only blows hot air, and temperature I can only set low or high, nothing in between

 

[JeepCares]

Hey OP did you ever figure out what when wrong? Mine just started to do the same. Only blows hot air, and temperature I can only set low or high, nothing in between

Have you brought this to the attention of a dealer yet, m3lover1? If not, we suggest doing so at your earliest convenience. If you need support while there, send our team a private message.

Kate
Jeep Cares

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