Should my APU come on automatically with i shut the truck off

#1
I have a 2012 Cascadia. When i shut the truck off should the TK APU start on its own.I have tried to set the selector to auto and it wont let me do that. I can only go from Heat, and A/C but not to auto. this is my first apu and i know nothing about it.
 

Tazz

Infidel
Supporter
#2
I have a 2012 Cascadia. When i shut the truck off should the TK APU start on its own.I have tried to set the selector to auto and it wont let me do that. I can only go from Heat, and A/C but not to auto. this is my first apu and i know nothing about it.
If you have it set on A.C. it should unless there is an additional master switch on the dash.
 

Ranger_375

Well-Known Member
#3
I have a 2012 Cascadia. When i shut the truck off should the TK APU start on its own.I have tried to set the selector to auto and it wont let me do that. I can only go from Heat, and A/C but not to auto. this is my first apu and i know nothing about it.
The APU will start on it's own if the voltage it's reading is below it's battery saving criteria, or if you have AC selected. If you don't want it to start, don't leave APU selected on the control panel, or otherwise turn it all the way off.

Freightliner or Internatitional it was wait until warning beep then hit the gas pedal.
Except that you have to continue to hit the brake or gas pedal to override. It's not a permanent override as a general rule, although it can be configured in many different ways.

I'll run my APU when I please. Running it means I'm not adding wear to the emissions system, and using less fuel to boot during breaks. Both add up to less cost of operation. Small part of why I got the truck I did.
 

mndriver

curmudgeon extraordinare
Supporter
#4
It kind of depends.

Have you got an Arctic kit on your system? In front of the Apu, there will be a manifold with two sensors on it. One has blue wires, (temp sensor) and one with white wires. ( Arctic kit sensor).

If it's equipped with the Arctic kit, and turns on immediately after turning off the truck, then the Arctic switch is bad. The one with the white wire.
 

Mike

Well-Known Member
Staff member
#5
the APU is not necessarily supposed to come on when the truck is shut off. My current unit doesn't do that, nor did my previous unit.

I believe it is something in the setup or programming, because I know some companies have their units where they start up as soon as the key is turned off. Either that, or they have a controller in the front of the cab where they can turn it on quickly before exiting the truck. Seen many companies where the driver pulls up to a fuel island, shuts the truck down, and the APU then seems to immediately fire up.
 

ironpony

Well-Known Member
Supporter
#6
Having the APU kick in automatically after shutting down the truck's engine is one of the options available with a TriPac. That's the way mine was set up.

Don't want that to happen? Just turn the APU "OFF" on the control panel. That's the button on the lower right corner of my control panel.

IMG_20170917_084848020.jpg


The APU controller is still on. It will not allow the engine to start, but also disables operation of the fan and a/c modes of operation.

If the heater is selected (as is in the picture) it WILL continue to operate even with the APU turned "OFF." The heater mode must be deselected, and the unit allowed to sequence through its shutdown procedure BEFORE starting the truck to allow it time to burn all of the fuel out if the burner chamber. That means pressing the mode switch (second from the left) until all the mode LEDs above it are "OFF." The picture shows the unit in heater mode - it's starting to get chilly at night. You need to do this about 5 minutes BEFORE starting your truck to allow sufficient time for the bunk heater to shut down properly. Failing to do this leaves fuel in the burner chamber that will carbonize, and leads to all the smoke you see coming out of the burner exhaust on some trucks.
 
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Mike

Well-Known Member
Staff member
#9
Mine isn't programmed to come on automatically, nor do I have a desire for it to be set that way. If I'm just running inside for a few minutes, the truck usually won't be that hot when I get back to it. Besides, it takes little time to cool it down once I start it back up, or get inside and turn the APU on if I am going to be parked for a while. Just wasted fuel to have it constantly running for no reason.

extreme cold? The arctic package will take care of all of this for me and start when there is a need for it.
battery voltage? Again, it will start for me if needed.
 

rigjockey

Token Canadian.
#10
Mine used to come on automatically, But I had the switch on the dash. It used to freak out homerland security at the border, They are kind of jumpy, So I would turn it off.
At customers that wanted the keys to the truck and the APU would come on, it freaked them out too because it was not a reefer.
:thefinger:Them!

I am really not adding much here but yeah, The APU would come on when the truck was turned off.
G'day.