2016 Ram 2500 heat passenger side none drivers ,purchased new two coolant changes one 75k ,new water pump and thermostat at 140k (besides when new)

[lusram]

Help truck at 155k ,purchased new May 2016 ,only heat on passenger side not driver,not dual zone ,5.7 ,had heat last winter ,great heat. Any suggestions?

 

[crash68]

Any suggestions?

It's most likely the heater core is partially plugged, there's quite a few posts on this particular issue.
Some people have luck back-flushing the heater core out, but others end up having to replace it.

 

[mtofell]

not dual zone

I had this exact issue on a Hyundai that was not dual-zone and it still ended up being something with an actuator door, flap, etc. It was under warranty so I didn't pay too much attention but it was curious that one side went out and it was a single zone system. Not sure if it has any relevance to Ram and your situation.

 

[GTyankee]

lusram,
open your lower glove compartment
remove the door & the lower glove box
while looking to your left
you will see a small motor/actuator
Watch this video

How to Replace Blend Door Actuator 2011-2018 RAM 2500

Buy Now!New Defroster Door Actuator from 1AAuto.com http://1aau.to/ia/1AZMX00204Watch this video to learn how to install a brand new TRQ blend door actuator ...

www.youtube.com

First use the HVAC controls to turn on heat, etc.
see if the actuator moves the White Lever
hopefully you do not hear a clicking sound

after he removes the actuator .. stop the video
using your thumb & finger, move the WHITE lever Up & Down, do hear/feel a weight & hear the thump as it reaches both limits.
( if you feel the weight & hear the thump, then the BLEND Door is OK )

There are 2 other actuators directly behind the HVAC Control panel.
They are directing the Air Flow through the vents, Floor, Chest, Dash Board Vents.

..............................................................................

IF your HVAC unit had Dual Controls for Passenger / Driver
That would mean removal of the whole HVAC Unit, or maybe there is a different way to measure Electrical current PULL on the actuator against the firewall ??

Dual Control HVAC Controls

 

[mtnrider]

It's a clogged heater core, all too common with these trucks. You can try flushing it (great videos on youtube on how to) but if that doesn't work it will have to be replaced.

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