A/C gets warm when stopped or at idle

[Bigsteve215]

This past Sunday my A/C wouldn't get cold when stopped or idling. Has been working perfect all summer and drove it for nearly 5 hours on Sunday, stopped to get gas and when I started her back up it wouldn't get cold. While driving it blows cold, not super cold but cold enough. Then when I stop at a traffic light the air starts getting warm until I start driving again. I searched the forum to see if anyone else has had this issue but did find anything. Truck is at the dealer now waiting for diagnose and fix. Anyone have any incite on the issue or have experienced the same thing?

 

[PowerJrod]

This past Sunday my A/C wouldn't get cold when stopped or idling. Has been working perfect all summer and drove it for nearly 5 hours on Sunday, stopped to get gas and when I started her back up it wouldn't get cold. While driving it blows cold, not super cold but cold enough. Then when I stop at a traffic light the air starts getting warm until I start driving again. I searched the forum to see if anyone else has had this issue but did find anything. Truck is at the dealer now waiting for diagnose and fix. Anyone have any incite on the issue or have experienced the same thing?

ETorque? When my Etorque kicks in and auto stops at a red light the AC compressor turns off ..which is normal

 

[Bigsteve215]

Turned off the start/stop and still got warm. When I remote start it, I get to the truck and its as if the A/C never kicked in and is just blowing cold air, then will get cold once I drive.

 

[Scram1500]

This past Sunday my A/C wouldn't get cold when stopped or idling. Has been working perfect all summer and drove it for nearly 5 hours on Sunday, stopped to get gas and when I started her back up it wouldn't get cold. While driving it blows cold, not super cold but cold enough. Then when I stop at a traffic light the air starts getting warm until I start driving again. I searched the forum to see if anyone else has had this issue but did find anything. Truck is at the dealer now waiting for diagnose and fix. Anyone have any incite on the issue or have experienced the same thing?

I experience the same thing in mine. I was going to do the AC hack, but it's decently cold while in motion. I do not have start/stop. There is some issue with the blend door that Ram has yet to acknowledge

 

[mikeru82]

I would try the AC hack if I was having any problems with my AC not blowing cold enough. I guess I'm one of the fortunate ones and my AC seems to work fine. I wouldn't call it ice cold, but it's sufficient so far this summer with temps in the upper 90's to low 100's. My suggestion is to try the AC hack if the dealership "doesn't find anything wrong".

 

[Nibis]

I'd have the Freon level checked.

 

[silver64]

There is a software update for the AC issue. I would also recommend when its super hot use the recirculate button and the air will stay much colder.

 

[Bigsteve215]

I have to have the truck back by Friday for a road trip. So if i get it back and they haven't 'fixed' the issue I'll try the hack. I would assume the dealer will check the freon but will make sure that done. I was thinking its a freon issue, or a fan isnt working properly when stopped.

 

[mikeru82]

I'd have the Freon level checked.

That would be a rather obvious thing for the tech to check. I wouldn't advise people to check this themselves unless they know what they are doing and have the right tools. Especially on a new truck with a warranty. Maybe if it's an old beater truck LOL. If the refrigerant on a brand new vehicle is low they'll need to address any leaks in addition to adding more refrigerant.

 

[Nibis]

That would be a rather obvious thing for the tech to check. I wouldn't advise people to check this themselves unless they know what they are doing and have the right tools. Especially on a new truck with a warranty. Maybe if it's an old beater truck LOL. If the refrigerant on a brand new vehicle is low they'll need to address any leaks in addition to adding more refrigerant.

I didn't suggest the OP do it themselves

 

[PowerJrod]

The other thing that came to my mind when said that the AC is back to cold when in motion is the fan....if the fan isn't kicking on then there will also be warm air or the compressor will just turn on then turn off. Vehicle in motion is basically a substitute for the fan.

 

[mikeru82]

I didn't suggest the OP do it themselves

Sorry, my bad. Apologies to you Nibis.

 

[UnloosedChewtoy]

The other thing that came to my mind when said that the AC is back to cold when in motion is the fan....if the fan isn't kicking on then there will also be warm air or the compressor will just turn on then turn off. Vehicle in motion is basically a substitute for the fan.

This is what I am thinking as well. Low on freon should mean A/C problems constantly or on-and-off, regardless of vehicle motion, in my experience. No A/C when idling/stopped, but works fine when moving, tells me the fan isn't doing its job.

If you keep an eye on vehicle temps (engine temp, oil temp, etc.), do they also start to climb when the vehicle is stopped?

 

[PowerJrod]

This is what I am thinking as well. Low on freon should mean A/C problems constantly or on-and-off, regardless of vehicle motion, in my experience. No A/C when idling/stopped, but works fine when moving, tells me the fan isn't doing its job.

If you keep an eye on vehicle temps (engine temp, oil temp, etc.), do they also start to climb when the vehicle is stopped?

Exactly! I agree about the low freon too... compressor would keep cycling. So either fan or something else computer/electrical I'd say in that sense.

 

[silver64]

Compressors will cycle until they get to the point where if there isn't enough refrigerant it stops so the compressor doesn't get damaged. Its also usually pretty easy to hear the compressor clutch clicking off & on. Another tip that most people aren't aware of is that if there is too much refrigerant the AC will not work properly either.

 

[SpeedyV]

Another tip that most people aren't aware of is that if there is too much refrigerant the AC will not work properly either.

Yes! Although this might be more common to find in home (central A/C) units.

 

[PowerJrod]

Compressors will cycle until they get to the point where if there isn't enough refrigerant it stops so the compressor doesn't get damaged. Its also usually pretty easy to hear the compressor clutch clicking off & on. Another tip that most people aren't aware of is that if there is too much refrigerant the AC will not work properly either.

I almost mentioned the "too much refrigerant" but didn't because he said it works fine once the vehicle is moving. If it was too much in the lines it wouldn't matter how fast the vehicle is moving.

 

[PowerJrod]

Yes! Although this might be more common to find in home (central A/C) units.

Had it happen to my VW CC....in AZ 112° degrees...smh

 

[Scram1500]

Maybe it's idle rpm related, an EPA fuel saving gremlin, could explain the software update

 

[FastBlackRam]

I can hear the fan under the hood "roaring" when my truck is stationary and the AC is blasting. Do you hear the fan running loudly when stopped? A good place to check this is at home where it is potentially quiet.

I have never actually checked but I am assuming there is a separate aux condenser fan from the engine cooling fan. If that guy is not working your symptom would be happening.