2013 RAM 1500 5.7 No heat in cab

[HWard]

Had a 2181 code pop up for the cooling system. Temperature was not registering in the gauge. I changed the thermostat (no coolant in thermostat location when it was removed and I did not drain coolant before removal) and no more code. Took radiator cap off to release any air trapped in system. No leaks and now I don't have any hot air in the cab. Fan pushes cool air when set on highest hot setting. Heater core not leaking on the floor either. Would the next step be to flush the system?

 

[crash68]

Being your truck is a 2013 with the Hemi, do you have the 8spd transmission (shift dial)?
If so there's a 3-way valve that directs the flow of coolant to the transmission TMU if the cab doesn't need heat. It's possible that valve isn't working.

The more likely cause is either air bound coil or the heater core is plugged. If you noticed that when the heat did work that the driver side would blow cooler air then the passenger side, this is a good indication that the heater core is plugged up. Back flushing may work but more likely it will need to be replaced.

 

[HWard]

I have the 6spd transmission. When the heat worked I had cooler air on the drivers side. Did think to check the passenger side at the time. Should there been evidence of coolant in the water pump housing when I removed the thermostat?

 

[crash68]

If the system wasn't full of coolant before removing the thermostat or water pump then the engine probably overheated and you could possibly have issues with head warpage and/or head gaskets leaking.

 

[Burla]

https://www.ramforum.com/threads/cooling-system-cleaners-aka-rmi-25.216426/

it's a leave in product, check overflow tank for debris after 500 miles.

could be a few things, could be clogged heater core, and if left untreated it can be fatal. Look up flushing heater core threads. If you run RMI 25 tun the heater a lot clean out the core.


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