In cab heat question

[Beasley907]

Question on heat. First winter with the ram, it was -15 out and ran the truck for 20 minutes and there was like zero heat coming out, usually it’s gradual warm air then hot as it warms up (in most trucks) Truck got up to operating temp and still no heat. Then all of a sudden heat kicked on and boom hot air at about minute 24 of it running. Is this a coolant bypass valve thing or a air in cooling system thing?

*update* tech said this is common with electronic coolant bypass valves. During these -20 cold snaps. He said mopar coolant bypass valves are worse than others. He said if it was my daily driver it would happen a lot less or wouldn’t happen at all. But said sense it went from cold to full hot instantly it’s likely just the coolant bypass valve sticking because it’s been sitting for 2 weeks in the cold. Said it’s common.

2015 ram 1500 5.7

 

[GTyankee]

How long have you had this Ram ?

If you had it last year at this time, was it doing this the same way then ?

Do you shut off the outside air, when you set your controls ?

 

[Rlaf75]

How long have you had this Ram ?

If you had it last year at this time, was it doing this the same way then ?

Do you shut off the outside air, when you set your controls ?

It says it's a 15 Ram 1500 5.7 and this is the first winter he or she has had it so it would appear it was recently purchased used.

 

[Rlaf75]

Question on heat. First winter with the ram, it was -15 out and ran the truck for 20 minutes and there was like zero heat coming out, usually it’s gradual warm air then hot as it warms up (in most trucks) Truck got up to operating temp and still no heat. Then all of a sudden heat kicked on and boom hot air at about minute 24 of it running. Is this a coolant bypass valve thing or a air in cooling system thing?

2015 ram 1500 5.7

Did this happen only one time or does it happen anytime the heat is on? You say zero heat. Was any air blowing from the vents or nothing blowing at all from the vents? If air was blowing out but it was cold air I would start by checking the coolant level in the radiator when the engine is COLD so you dont burn yourself. If coolant level is full then it could be the actual control switch that is bad. If no air is coming from the vents on any fan speed I would check to make the blower motor is not crazy hot to the touch. It could be binding up and eventually free enough to blow the heat. There's also a resister that controls the fan. A faulty resistor will usually allow the fan to work only on high speed and no other. The dash control switch could still be bad if no air is blowing from the vents. Without actually getting it diagnosed it will be difficult to pin point the problem

 

[Beasley907]

Did this happen only one time or does it happen anytime the heat is on? You say zero heat. Was any air blowing from the vents or nothing blowing at all from the vents? If air was blowing out but it was cold air I would start by checking the coolant level in the radiator when the engine is COLD so you dont burn yourself. If coolant level is full then it could be the actual control switch that is bad. If no air is coming from the vents on any fan speed I would check to make the blower motor is not crazy hot to the touch. It could be binding up and eventually free enough to blow the heat. There's also a resister that controls the fan. A faulty resistor will usually allow the fan to work only on high speed and no other. The dash control switch could still be bad if no air is blowing from the vents. Without actually getting it diagnosed it will be difficult to pin point the problem

Air is blowing fine, coolant level is fine. I did a coolant flush last summer and replaced with OEM coolant. I did re check coolant and it’s full. Switch is working blower settings etc. it’s strange It’s not normal signs of a bad heater core, or anything. Almost seems like air in the system but I burped it properly during the coolant change and I’ve put hundreds of miles on since then so no air is in there. Not sure if this is a ram thing or what.

 

[Beasley907]

How long have you had this Ram ?

If you had it last year at this time, was it doing this the same way then ?

Do you shut off the outside air, when you set your controls ?

Outside air is off, first winter with it. It’s closer to -20 so I mean it’s pretty cold.

 

[GTyankee]

This may or may not help

2013 Dodge Ram a/c control head

Please use the following link when ever using Amazon.com. Any purchases you make on Amazon will help support this channel.http://amzn.to/2mALgqSEveryone love...

www.youtube.com

 

[TestPilot57]

Not sure if this is a ram thing or what.

Definitely not a Ram thing. I had a 2015 and now a 2020 and they both produce heat amazingly fast (though still gradual, as you would expect) compared to any other vehicle I've driven.

 

[crash68]

You might want to scan for pending or historical error codes. If the bypass valve sticks it can throw a P26AB code

 

[Dean2]

It gets very cold here too. Set your heat to maximum, blower to top 1/3 of range, air distribution to wherever you want it and make sure that AUTO is NOT engaged. These damn trucks are so smart now they won't pump hot air until it gets warn enough to hit the temp setting. If you leave auto off, it will pump whatever temp coolant it has through the heater.
Plugging in the block heater will shorten warm up period by a whole bunch and a 120 volts in car warmer makes another big difference.

 

[Beasley907]

You might want to scan for pending or historical error codes. If the bypass valve sticks it can throw a P26AB code

Changed bypass valve last summer as well.

 

[Rlaf75]

Air is blowing fine, coolant level is fine. I did a coolant flush last summer and replaced with OEM coolant. I did re check coolant and it’s full. Switch is working blower settings etc. it’s strange It’s not normal signs of a bad heater core, or anything. Almost seems like air in the system but I burped it properly during the coolant change and I’ve put hundreds of miles on since then so no air is in there. Not sure if this is a ram thing or what.

Ok so the air is blowing good but the temp control unit (hot to cold) may be bad. Its possible that a blend door actuator may be bad too

 

[crash68]

The function of the bypass valve is to divert coolant to the transmission TMU if not requested by the cab heat. Although I haven't found it's exact control parameters.
Does this truck have the dual zone climate control or the ATC single zone mod?
If the weather is frequently below zero you could get the winter front(82213959AC) for the EcoDiesel to speed warm up especially if your typical trips are short.

 

[Beasley907]

The function of the bypass valve is to divert coolant to the transmission TMU if not requested by the cab heat. Although I haven't found it's exact control parameters.
Does this truck have the dual zone climate control or the ATC single zone mod?
If the weather is frequently below zero you could get the winter front(82213959AC) for the EcoDiesel to speed warm up especially if your typical trips are short.

It’s not my daily, I have a little car I drive around. It doesn’t have dual climate it’s a base model. CoolNt flushed last summer, new coolant bypass valve last summer.

Im stumped.

 

[Beasley907]

Question on heat. First winter with the ram, it was -15 out and ran the truck for 20 minutes and there was like zero heat coming out, usually it’s gradual warm air then hot as it warms up (in most trucks) Truck got up to operating temp and still no heat. Then all of a sudden heat kicked on and boom hot air at about minute 24 of it running. Is this a coolant bypass valve thing or a air in cooling system thing?

2015 ram 1500 5.7

*update* tech said this is common with electronic coolant bypass valves. During these -20 cold snaps. He said mopar coolant bypass valves are worse than others. He said if it was my daily driver it would happen a lot less or wouldn’t happen at all. But said sense it went from cold to full hot instantly it’s likely just the coolant bypass valve sticking because it’s been sitting for 2 weeks in the cold. Said it’s common.

 

[Beasley907]

You might want to scan for pending or historical error codes. If the bypass valve sticks it can throw a P26AB code

*update* tech said this is common with electronic coolant bypass valves. During these -20 cold snaps. He said mopar coolant bypass valves are worse than others. He said if it was my daily driver it would happen a lot less or wouldn’t happen at all. But said sense it went from cold to full hot instantly it’s likely just the coolant bypass valve sticking because it’s been sitting for 2 weeks in the cold. Said it’s common.

 

[TestPilot57]

These damn trucks are so smart now they won't pump hot air until it gets warn enough to hit the temp setting. If you leave auto off, it will pump whatever temp coolant it has through the heater.

Not my experience at all.

My 2015 was parked in a(n) insulated, but not heated garage. It would never get to to below 0 (F), but certainly below freezing. I would start it on my way out to the garage, having opened the door on my way out. So it was running maybe 15-30 seconds before I started backing out. I would immediately get in, back out and head to work. Within 1/2 mile the coolant temp would be 100° and the (auto) fan would start coming up. Within 1 mile the fan would be be putting noticeable heat out.

My 2020 is parked overnight in our semi-heated (40°) garage. But the experience is the same. As soon as the coolant is up to about 100° the fan starts coming up. Once it's to 120° or so the fan is at moderate speed and there is real heat coming out. Same thing at end of day coming home, when it can be below to well-below 0°F.

 

[Dean2]

Not my experience at all.

My 2015 was parked in a(n) insulated, but not heated garage. It would never get to to below 0 (F), but certainly below freezing. I would start it on my way out to the garage, having opened the door on my way out. So it was running maybe 15-30 seconds before I started backing out. I would immediately get in, back out and head to work. Within 1/2 mile the coolant temp would be 100° and the (auto) fan would start coming up. Within 1 mile the fan would be be putting noticeable heat out.

My 2020 is parked overnight in our semi-heated (40°) garage. But the experience is the same. As soon as the coolant is up to about 100° the fan starts coming up. Once it's to 120° or so the fan is at moderate speed and there is real heat coming out. Same thing at end of day coming home, when it can be below to well-below 0°F.

Yep, that is precisely what I mean about being smart. 100 degree coolant will easily produce the heat you need in the cab. The smart part is it doesn't crank the fan until the coolant has the ability to deliver. At -40 parked outside it takes way more than a couple of minutes to get coolant to 100 degrees unless u have the block heater plugged in.

If you take it off auto you can set the fan wherever u like it and it will pump out whatever heat that is available. That is how u bypass the smart function.

 

[TestPilot57]

Yep, that is precisely what I mean about being smart. 100 degree coolant will easily produce the heat you need in the cab. The smart part is it doesn't crank the fan until the coolant has the ability to deliver. At -40 parked outside it takes way more than a couple of minutes to get coolant to 100 degrees unless u have the block heater plugged in.

If you take it off auto you can set the fan wherever u like it and it will pump out whatever heat that is available. That is how u bypass the smart function.

Granted, I rarely have opportunity to experience the type of conditions you quote.

But are you saying that, on Auto, it won't start putting out heat until the coolant is up to at least the set temp? IOW, if it's -40 and your set temp is 70, it won't start putting out heat until the coolant is at least +70?

Like I said, it would be rare for me to have a similar situation, but for sure there have been plenty of times when I didn't remote start at the end of the day and went out well before coolant was at my set temp. Maybe I didn't notice because I also have heated seats and steering wheel, and because I don't have the extreme temps it was only a minute or two before coolant was above set temp. But that just seems like a "so smart that it's dumb" kind of programming thing that could be easily fixed. As long as coolant temp is above cabin temp, send it in! Basic, simple, should be implemented if it's not. @RamCares

 

[Beasley907]

Granted, I rarely have opportunity to experience the type of conditions you quote.

But are you saying that, on Auto, it won't start putting out heat until the coolant is up to at least the set temp? IOW, if it's -40 and your set temp is 70, it won't start putting out heat until the coolant is at least +70?

Like I said, it would be rare for me to have a similar situation, but for sure there have been plenty of times when I didn't remote start at the end of the day and went out well before coolant was at my set temp. Maybe I didn't notice because I also have heated seats and steering wheel, and because I don't have the extreme temps it was only a minute or two before coolant was above set temp. But that just seems like a "so smart that it's dumb" kind of programming thing that could be easily fixed. As long as coolant temp is above cabin temp, send it in! Basic, simple, should be implemented if it's not. @RamCares

My coolant was to lean I’m in the process of getting more concentrate in. Ran several yesterday with 2 testers and it was too lean after my flush last summer