AC issue in Texas heat.

[Mexadian]

So i bought a 2019 Ram 1500 Classic Warlock in March 2020 (New 58 miles) and had a AC issue today. Went to work at 6am AC working fine. Get in my car at 4pm to head home from work and AC doesn't turn on (No Blower, No noise, nothing). Make the hot drive home and get to looking at fuses and relays. None are blown, switched the relays around still nothing, ran a scan tool no codes or anything and I put presure on various points of the fuse box to see if its a bad connections and nothing.Its July in Texas with a heat index of 100+, so I go inside to cool down and call the dealership to make an appointment to bring it in. Around 930pm go to check the truck and magically the AC working now. I have a theory that that excessive Texas heat is causing the fuses or relays to fail and once they cool down they work normal. Anyone else have this kind of issue?

 

[Hootbro]

From my experience, most times when a AC system fails to turn on, it is usually driven by the low pressure switch circuit. Than can mean low to marginal Freon charge and/or a electrical problem with the low pressure switch circuit itself.

The hotter the outside temp, the more likely a low or marginal Freon charge will trip the low pressure switch and give intermittent AC function. If it was me, I would still make a warranty visit and have them put a set of gauges on it and check the charge.

Most new vehicles to include RAM now have the R1234yf refrigerant that is replacing the R134a refrigerant. So expected Freon charge pressure ranges will be different.

 

[KeepRight]

From my experience, most times when a AC system fails to turn on, it is usually driven by the low pressure switch circuit. Than can mean low to marginal Freon charge and/or a electrical problem with the low pressure switch circuit itself.

The hotter the outside temp, the more likely a low or marginal Freon charge will trip the low pressure switch and give intermittent AC function. If it was me, I would still make a warranty visit and have them put a set of gauges on it and check the charge.

Most new vehicles to include RAM now have the R1234yf refrigerant that is replacing the R134a refrigerant. So expected Freon charge pressure ranges will be different.

Yup awesome post...

 

[JB1]

I’m in Houston and it’s been hot as hell this week. Snapped this pic as I got out of my truck the other day at 105 degrees at 4pm

 

[KeepRight]

I’m in Houston and it’s been hot as hell this week. Snapped this pic as I got out of my truck the other day at 105 degrees at 4pm

View attachment 215552

Yup... I'm up here in N. Texas... As a Damn Yankee, I do love Texas - except July to Oct.

It wasn't that hot... The truck was parked outside open lot with windows up... Direct sun in the middle of Aug 2019.

[emoji35][emoji91][emoji91]

 

[JB1]

Yup... I'm up here in N. Texas... As a Damn Yankee, I do love Texas - except July to Oct.

It wasn't that hot... The truck was parked outside open lot with windows up... Direct sun in the middle of Aug 2019.

[emoji35][emoji91][emoji91]

Damn now that’s hot

I gotta move my son back to TTU in Lubbock next month, this was the temp Tuesday.

 

[MRFREEZE57]

From my experience, most times when a AC system fails to turn on, it is usually driven by the low pressure switch circuit. Than can mean low to marginal Freon charge and/or a electrical problem with the low pressure switch circuit itself.

The hotter the outside temp, the more likely a low or marginal Freon charge will trip the low pressure switch and give intermittent AC function. If it was me, I would still make a warranty visit and have them put a set of gauges on it and check the charge.

Most new vehicles to include RAM now have the R1234yf refrigerant that is replacing the R134a refrigerant. So expected Freon charge pressure ranges will be different.

in a refrigeration system the cold weather will usually cause the low pressure control to open, in the hot weather more likely to short cycle on low pressure if low on gas. you need to connect a set of gauges to really see what is going on.

 

[indept]

It doesn't sound like a freon problem since the blower doesn't come on either. I'm wondering if it not a problem of the system not "booting" up correctly or the ignition switch isn't making connection for the accessories. If it happens again, shut the truck off wait a minute then restart it.

 

[MRFREEZE57]

It doesn't sound like a freon problem since the blower doesn't come on either. I'm wondering if it not a problem of the system not "booting" up correctly or the ignition switch isn't making connection for the accessories. If it happens again, shut the truck off wait a minute then restart it.

that is true if your fan is not running you will not get cold air. you can check if the compressor is coming on, especially if the fan is not running and the compressor is, the suction line ( the bigger of the two) will be very cold to touch. just looked under the hood on my truck there is no low pressure switch I can see, does a high pressure cut out though.

 

[Sandevino]

Just outside of Dallas here and this makes me appreciate my old skool manual a/c in my 2020 2500 tradesman.

I too doubt this is a mechanical issue. My wife’s Jeep Grand Cherokee would do this from time to time. That last time it happened I popped the hood, checked the system with my gauges and all was good.

We restarted the vehicle rebooting the Uconnect brain and everything worked perfectly.

Next time it happens, restart the vehicle and the issue should be resolved.

 

[Joshua Collins]

Honestly carry a 10mm wrench in the door for this and uconnect issues disconnect the battery briefly and its good again for who knows how long. Have a 19 classic as well and they have already replaced the radio once which controls the climate as well. Way too hot in the Houston area for the ac to be going out.

 

[WhiteExpress]

I 100% agree on restarting the truck or if need be, disco the battery. If you were getting warm air, I'd think it was freon related. Fortunately / Unfortunately it's a '19 and really, it's the dealers problem.

I'd make sure they've updated the firmware (if available) on everything. Could be a bogus string of code somewhere. #modernmechanics

 

[Mexadian]

Took it to the dealer to check it out and get the recall work done on it and they couldn't find any problems with it so time will tell.

 

[Mexadian]

It happened again today so I took it directly to the dealer. Also noticed the Back up camera and Satellite radio stopped working also so make me think it’s the Uconnect system.

 

[Sherman Bird]

So i bought a 2019 Ram 1500 Classic Warlock in March 2020 (New 58 miles) and had a AC issue today. Went to work at 6am AC working fine. Get in my car at 4pm to head home from work and AC doesn't turn on (No Blower, No noise, nothing). Make the hot drive home and get to looking at fuses and relays. None are blown, switched the relays around still nothing, ran a scan tool no codes or anything and I put presure on various points of the fuse box to see if its a bad connections and nothing.Its July in Texas with a heat index of 100+, so I go inside to cool down and call the dealership to make an appointment to bring it in. Around 930pm go to check the truck and magically the AC working now. I have a theory that that excessive Texas heat is causing the fuses or relays to fail and once they cool down they work normal. Anyone else have this kind of issue?

Go in the house and find the "Iditerod" movie. The heat will somehow bother you less!

Seriously, this is a problem I've seen recently on FCA products. Because they are all intermittent, the customers are reluctant to spend money on a not-too-sure thing. I think because the blower fails to come on in all those I've seen, I'm leaning towards a blower control... but that's a mere extrapolation.

 

[JimE]

It happened again today so I took it directly to the dealer. Also noticed the Back up camera and Satellite radio stopped working also so make me think it’s the Uconnect system.

The real problem is the truly jink switches and connectors associated with U-Connect. 100% crap! Even worse than found on GM products, never thought that possible. With 3 FCA products of 2014, 2017, and 2019 year models and all have had issues associated with U-Connect and the rotten switches have always been the cause of the issue. Believe it or not in two cases rotating the volume control several times may solve the problem. Otherwise try punching the MUTE button several times. Sadly FCA dealers have very limited diagnostic tools available to them and there technicians seem to lack basic electrical circuit knowledge.

 

[Gone]

Every time i buy a new car or truck I always open up the fuse box and push in all the fuses..

 

[SVTII]

Damn now that’s hot

I gotta move my son back to TTU in Lubbock next month, this was the temp Tuesday.

View attachment 215554

I’m sorry your son’s going to TTU AND you have to visit the Hub City! Just pulling your leg a little.
There are two things I miss about Lubbock; 1, being able to get across town in 15-20 minutes. And 2, the dry heat.

 

[JB1]

I’m sorry your son’s going to TTU AND you have to visit the Hub City! Just pulling your leg a little.
There are two things I miss about Lubbock; 1, being able to get across town in 15-20 minutes. And 2, the dry heat.

One thing I noticed about Lubbock, I've never seen so many new car dealerships in that size of city/population. The West and SW side is booming with a lot of new dealerships, restaurants, hotels etc.

Guns Up

 

[Butch27]

This was at start up a couple weeks ago, cooled down to 109° in New Braunfels. Sorry about your AC, I'm old and use the manual dial and temp set buttons. Good luck and keep posted on outcome.