Freightliner Cascadia '20 bunk heater not heating

Interior comfort mode is still working when engine stops. It should restart the engine when sleeper cools down some. The dash heater and fan control don't work. Everything is run from the sleeper controls. Their is a temperature sensor in sleeper. If you turn sleeper fan on halfway. It will keep air moving even when engine stops in the sleeper. Then when engine starts again the front dash fan will come on also at same speed as sleeper fan setting.

When the engine stops the diesel burning heater is supposed to turn on and take over and run on the batteries for 6-8 hours. If that heater won't fire up then it should start the engine again once sleeper cools some.

I usually set heat side to 3 o'clock in sleeper and set fan speed to 10 o'clock

 

I had to have the diesel bunk heater repaired on my 2021 just a few weeks ago. It took some persuasion to even get my service manager to even go out to my truck to confirm that the epu diesel heater did not work. Unfortunately, I was not privy to what was involved in the actual repairs. I'm working on that.

As for your truck, its a new truck, it should be under warranty. Pester your road service or service manager to get it fixed. In the meantime, in comfort mode, the truck runs main engine when the temp falls something like 5 degrees below your thermostat setting when in the heat mode.

 

My company shop replaced my heater on my 2020 at about 180,000 miles. They said when you turn the heater off or it turns off by itself. It shuts down completely and basically is overheating. They say said it was turning into heatsink. Because it won't pump the coolant to cool the heater. They said freightliner needs to reprogram them or they should pay for the $800 replacement heater

 

Hey,
Did you get that matter resolved?
I am having same issue.Thanks

 

Hello Dennis,

I am getting the same problem with on my Freightliner Cascadia. The heat keeps running for 10-15 minutes and then it blows cold air. If I again turn the fan off and turn it on, it goes for 10-15 minutes again. What could be wrong. I believe you figured what was wrong on your truck. If anyone can help. Thank you

 

My heater stopped working recently and turned out to be the batteries.

 

Yea same issues in my 2019 cascadia with parksmart. My a/c runs whenever I press the Park button in the back with or without optimized idle. But the heat will never work. I replaced fuel pump 300$. I replaced hvac controller 177$ and with or without optimized idle my pump will not click and the heater underneath truck never makes a d... sound. Is replacing the heater next?

 

Well after further examination turns out it wasn't the batteries. They reset something with there computer and it worked once but then didn't work the second time I tried it. So I took it back to the TA and they said they think it's the ignitor screen that needs to be cleaned. But they don't do that sort of thing. Said it's out of there scope of repair. So it's sitting at the freightliner liner right now. Told them what the TA said and so there working on it hopefully tomorrow. Will see if that fixes it.