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A/C Performance

Today I decided to just see what the vehicle was capable of with settings on LO, recirculate and FAN was on 4. The center stack drivers vent would not get below 57 and the center stack passenger vent was 46. The left most drivers vent would get down to 52 or so. Temp outside was 95 and I drove it around for about 20-30 minutes. Overall I don't think it's miserable but what I have said since ownership of about 1 year now is that it is not up to par with other vehicles. It is disappointing to have drawn all these accolades YET deliver poor performance on a critical item.

In my vehicles I like to set it to Auto but this A/C is too unpredictable with fan speed and the temp is all over the board. This vehicle takes too long to start cooling compared with other vehicles. Tomorrow I am taking it in for the TSB that is applicable for my VIN with the corrected updated bulletin.

BTW just bought a 2019 Pilot Elite AWD last weekend and the A/C is up to Honda spectacular standards as usual.
 
Today I decided to just see what the vehicle was capable of with settings on LO, recirculate and FAN was on 4. The center stack drivers vent would not get below 57 and the center stack passenger vent was 46. The left most drivers vent would get down to 52 or so. Temp outside was 95 and I drove it around for about 20-30 minutes. Overall I don't think it's miserable but what I have said since ownership of about 1 year now is that it is not up to par with other vehicles. It is disappointing to have drawn all these accolades YET deliver poor performance on a critical item.

In my vehicles I like to set it to Auto but this A/C is too unpredictable with fan speed and the temp is all over the board. This vehicle takes too long to start cooling compared with other vehicles. Tomorrow I am taking it in for the TSB that is applicable for my VIN with the corrected updated bulletin.

BTW just bought a 2019 Pilot Elite AWD last weekend and the A/C is up to Honda spectacular standards as usual.
Great that you documented actual vent and ambient temps before service. With that passenger vent at 46 degrees that shows the evaporator is good and cold. I bet if you used a temporary non damaging clamp on "out" hose from water pump to heater core, you would drop both center vents to 38-42 range within 15 minutes. Update us on measurements after service TSB. I wish all members would get real thermometer numbers. Most kitchens have a meat probe thermometer these days for barbecuing.
 
Great that you documented actual vent and ambient temps before service. With that passenger vent at 46 degrees that shows the evaporator is good and cold. I bet if you used a temporary non damaging clamp on "out" hose from water pump to heater core, you would drop both center vents to 38-42 range within 15 minutes. Update us on measurements after service TSB. I wish all members would get real thermometer numbers. Most kitchens have a meat probe thermometer these days for barbecuing.
My center stack drivers vent is 56 and the center stack passenger vent is 48.
 
Where can I find a clamp and some pics where to put it?
 
Where can I find a clamp and some pics where to put it?
 
Check out this thread, for lots of ideas.
 
Got the TSB done today and no change on vent temps. Still about 11 degree difference between center stack vents.
 
Got the TSB done today and no change on vent temps. Still about 11 degree difference between center stack vents.
And therein lies the problem. Their TSB fix does not solve the problem. It’s over 90 degrees here in Central Texas today, and I don’t know that I can recommend a new Ram to family and friends.
 
CLAMP the heater core hose like the rest of us have. Instant gratification.

And therein lies the problem. Their TSB fix does not solve the problem. It’s over 90 degrees here in Central Texas today, and I don’t know that I can recommend a new Ram to family and friends.
 
We've had several 90 degrees days here lately in TN. I have vent temps in the 40's.

And therein lies the problem. Their TSB fix does not solve the problem. It’s over 90 degrees here in Central Texas today, and I don’t know that I can recommend a new Ram to family and friends.
 
CLAMP the heater core hose like the rest of us have. Instant gratification.

Pulled the trigger on the clamps finally. Been watching for a week to see if something crazy happened. Guess it's the fix until Ram figures this out. For $15, it's worth it.
 
Has anyone actually reported they get consistent vent temps on both vents in the 40's without modifying anything?
 
We've had several 90 degrees days here lately in TN. I have vent temps in the 40's.
For those of you with later build dates that have cold AC, congrats! I’ve got a clamp on my out hose, as do many of us, and today it barely got below 50 degrees with an outside temp of 91. Without the clamp, I doubt it would get below 53 - 54 degrees. Sounds like FCA engineers figured out the problem and corrected it in your trucks.
 
For those of you with later build dates that have cold AC, congrats! I’ve got a clamp on my out hose, as do many of us, and today it barely got below 50 degrees with an outside temp of 91. Without the clamp, I doubt it would get below 53 - 54 degrees. Sounds like FCA engineers figured out the problem and corrected it in your trucks.

Not so fast. My new 2019 2500 build date was 4/19/2019. Took it into the dealer with 63°F on the driver's center vent, and 55°F on the passenger vent on an 81°F day. The service rep hadn't heard of this problem yet, but that can't be possible. After confirming good high/low refrig pressures, they "recalibrated" the blend doors. I have no idea what that really means, calibration is not the right word. Anyway, now I get 62°F driver and 54°F passenger on the center console with 93°F ambient. Better, but that 62°F was after 20 minutes of cooldown with RPMs at 1500.

The service rep used an IR gun and called the driver's vent 43°F. If anything needs to be recalibrated, it is the service tech's IR thermometer! I validated calibration on my probe by ensuring that it read the same air temperature as the RAM, and then checked if it read freezing in icewater. (It read 34°F in the equilibrium ice bath.) So, for my thermometer, the calibration "zero" is -2°F, and the calibration "span" is 1.043 °/°, which basically means the calibration is valid for thermometer accuracy to within 2 F° between 32°F - 81°F.

So, now I have two problems: my A/C is working unacceptably poorly on my brand new HD RAM, and the dealer techs do not have the tools to properly diagnose the issue. I suppose I could ask to witness the temperature reading at the dealer...

EDIT: It is possible that the dealer IR gun read a cold temperature, and then as soon as the engine was shut off, the blend door "calibration" reverted back to the misaligned setting. Could be why my temps are back up. I will give the dealer the benefit of the doubt.
 
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I think your dealer is bull*****ing you!!!

Not so fast. My new 2019 2500 build date was 4/19/2019. Took it into the dealer with 63°F on the driver's center vent, and 55°F on the passenger vent on an 81°F day. The service rep hadn't heard of this problem yet, but that can't be possible. After confirming good high/low refrig pressures, they "recalibrated" the blend doors. I have no idea what that really means, calibration is not the right word. Anyway, now I get 62°F driver and 54°F passenger on the center console with 93°F ambient. Better, but that 62°F was after 20 minutes of cooldown with RPMs at 1500.

The service rep used an IR gun and called the driver's vent 43°F. If anything needs to be recalibrated, it is the service tech's IR thermometer! I validated calibration on my probe by ensuring that it read the same air temperature as the RAM, and then checked if it read freezing in icewater. (It read 34°F in the equilibrium ice bath.) So, for my thermometer, the calibration "zero" is -2°F, and the calibration "span" is 1.043 °/°, which basically means the calibration is valid for thermometer accuracy to within 2 F° between 32°F - 81°F.

So, now I have two problems: my A/C is working unacceptably poorly on my brand new HD RAM, and the dealer techs do not have the tools to properly diagnose the issue. I suppose I could ask to witness the temperature reading at the dealer...
 
I think your dealer is bull*****ing you!!!
@greg, that is my last resort. I hope they are just chasing a really nasty engineering problem, and it is getting the best of them. It wouldn't be the first time a problem did that.
 
Not so fast. My new 2019 2500 build date was 4/19/2019. Took it into the dealer with 63°F on the driver's center vent, and 55°F on the passenger vent on an 81°F day. The service rep hadn't heard of this problem yet, but that can't be possible. After confirming good high/low refrig pressures, they "recalibrated" the blend doors. I have no idea what that really means, calibration is not the right word. Anyway, now I get 62°F driver and 54°F passenger on the center console with 93°F ambient. Better, but that 62°F was after 20 minutes of cooldown with RPMs at 1500.

The service rep used an IR gun and called the driver's vent 43°F. If anything needs to be recalibrated, it is the service tech's IR thermometer! I validated calibration on my probe by ensuring that it read the same air temperature as the RAM, and then checked if it read freezing in icewater. (It read 34°F in the equilibrium ice bath.) So, for my thermometer, the calibration "zero" is -2°F, and the calibration "span" is 1.043 °/°, which basically means the calibration is valid for thermometer accuracy to within 2 F° between 32°F - 81°F.

So, now I have two problems: my A/C is working unacceptably poorly on my brand new HD RAM, and the dealer techs do not have the tools to properly diagnose the issue. I suppose I could ask to witness the temperature reading at the dealer...
The IR gun probably sees the cold plastic ducts physical temp as opposed to air flow temp that a probe type thermometer (either electronic digital or mechanical dial) would read. I think they are an IR surface temp technology. Here is one of several members workarounds. Perform at your own risk. This is for 2019 1500 but should be similar on classic truck. Don't cut your heater hoses so you can later remove modification without a trace when Ram comes up with proper resolution. At least you can get immediate summer heat relief.IMG_3083.jpg
 
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